Gwen Stefani admits she is "really jealous" of Christina Aguilera.
The 'Baby Don't Lie' hitmaker is upset that she hand back her role as a mentor on 'The Voice' USA to the 33-year-old beauty next year, as the 'Your Body' singer has had a rotating spot on the panel since the series began in 2011.
The 45-year-old star confessed: "I feel really jealous of Christina. I feel weird that they are doing it without me."
The No Doubt star says she will definitely miss the show because she really enjoyed it.
She told E! News: "I got so much out of this, way more than I ever thought."
Christina, who gave birth to daughter Summer Rain in August with fiancé Matthew Rutler and has son, Max, six, with ex-husband Jordan Bratman, has already started shooting season eight of the reality singing competition, which will air next spring.
A source previously claimed she was worried Gwen might be offered a permanent spot on the panel.
The insider said: "Christina is extremely threatened by [her temporary replacement] Gwen. She knows that if the ratings are higher on Gwen's season than they were on hers, the producers may have no choice but to ask Gwen to stay on.
"She's ready to fight for her spot."

Dr. Luke wants allegations that he sexually assaulted Kesha to be dismissed from their court battle.
Lawyers for the music producer, who is counter-suing the 'Tik Tok' hitmaker after she filed legal documents seeking to have their record contract dissolved and accused him of sexually, physically, verbally and emotionally abusing her for almost a decade, have argued that Kesha's claim that she was raped by him is barred by the statute of limitations because it could not have occurred within the past two years.
The music executive's lawyers are also seeking to have a claim of gender violence thrown out because it has a three-year statute of limitations.
Responding to the filing, Kesha's lawyer Mark Geragos said: "Dr. Luke is hiding behind a legally flawed motion which we expect won't work."
The 'Blow' hitmaker denied during a deposition for an unrelated lawsuit in 2011 that Dr. Luke - real name Lukasz Gottwald - had made any sexual advances towards, but her lawyer said the producer threatened her would hurt her if she ever discussed the alleged rape.
If dismissed, six other allegations including sexual harassment, civil harassment and intentional infliction of emotional distress will remain in the civil case unless the music producer files separate motions.
Dr. Luke is also suing Kesha's mother, Pebe Serbet, claiming she orchestrated a smear campaign of lies against him and tried to extort him in a desperate attempt to get the 27-year-old singer out of her contract with him.

Jennifer Aniston and Justin Theroux were very affectionate during a romantic date in New York City.
The couple, who got engaged in August 2012 and are rumoured to be considering getting married in the city next month, watched six performances at the 24 Hour Plays event on Monday night (17.11.14), where they were spotted cuddling up together.
An eyewitness said the 'Horrible Bosses 2' actress, 45, and 'The Leftovers' actor, 43, "were very discreet when they walked in and they sat in the balcony of the theatre."
The source also told E! News: "Jennifer was wearing glasses and Justin was in his staple leather jacket. They were both sitting closely together. Justin had his hand around her and they were both laughing over the funny performances. It was a true date night!"
The couple recently flew back to the US from London, where they attended the premiere of Jennifer's new comedy last week.
'Les Miserables' Amanda Seyfried, 28, and boyfriend Justin Long, 36, were also at the event and performed in one production before joining Aniston and Theroux on the balcony, where they also showed off "major PDA [Public Displays of Affection]."
The eyewitness added: "Justin and Amanda were so sweet."

Scarlett Johansson's family is the biggest source of joy in her life.
The 29-year-old actress, who gave birth to her first child, Rose, six weeks ago, also says her French fiancé Romain Dauriac makes her laugh.
Asked what brings her the greatest joy, the 'Her' star said: "My family. And Key lime pie."
In a list of 20 questions for Marie Claire magazine, the blonde beauty also revealed what makes her cry, saying: "Thoughtfulness and my sister's sentimentality."
Scarlett, who was previously married to Ryan Reynolds, would like to have dinner with Bono, David Bowie and the late actress Bette Davis.
The 'Vicki Cristina Barcelona' star says the best gift she's ever received was from the movie's director, Woody Allen, who gave her his iconic glasses.
She is also a huge fan of "acupuncture" and would love to take a "three-month tour of India," even though she feels like "moving" is on her perennial to-do list.
The actress, who relocated to Paris last year, moved back to New York City shortly before giving birth to Rose in early September and a source previously revealed she is now searching for a new home in Los Angeles.
Meanwhile, now that she is a mother, Scarlett admits her greatest indulgence is "taking a long bath followed by a long nap."

Justin Bieber has cleared his schedule to study the Bible.
The 20-year-old star, who was arrested for DUI [Driving Under the Influence] in Miami earlier this year and also charged with vandalising his former neighbour's home with eggs in Calabasas, California, is reportedly staying at the Rancho Mirage close to Palm Springs, California for two weeks with his pastor, as he wants to firmly reconnect with his religious beliefs.
A source said the 'Baby' hitmaker, who recently split from his on-again, off-again girlfriend Selena Gomez, is on a "mission" to learn how to spread the word of God and has exiled himself from his friends, alcohol and marijuana for the remainder of November.
The Canadian singer - who identifies himself as a Christian - was spotted outside the luxurious resort with the book 'Occupy All Streets,' which teaches how to resist bad temptations, on Monday (17.11.14), according to gossip website TMZ.com.
Justin has surrounded himself with spiritual mentors in recent months, including pastor Carl Lentz of Hillsong New York City, who previously insisted he is a "good kid" despite his bad behaviour.
He told CBN in August: "With Justin, it's not my job to be his police officer. It's my job to be a friend to him, and that's all I am."
Justin also frequently attended pastor Judah Smith's Bible study at the City Church in Los Angeles with the 'Heart Wants What It Wants' hitmaker Selena, 22, over the summer.

Blake Lively's best friend is envious of Ryan Reynolds.
Amber Tamblyn, who has been close pals with the 27-year-old pregnant actress since they co-starred together in the 'Sisterhood of the Travelling Pants' in 2005, thinks she is going to be an "incredible" mother and her husband is lucky to have her.
She quipped: "I would love to have a child with Blake Lively. Absolutely. I mean I'm in line. I'll be the next one, I would be pummelling Ryan in the face to get [him] out of the way. So I can get to her uterus."
The 31-year-old actress has no doubt Ryan and Blake will be great parents.
She told UsMagazine.com at the Save a Child's Heart event in Los Angeles: "They're going to be incredible. They're going to be really, really, really incredible. Blake's going to be more like the dad, and Ryan's going to be more like the mom. And that just means very emotional, and he's growing his hair out."
Amber, 31, and her husband, David Cross, frequently enjoy double dates with Blake and Ryan, 38, and reunions with their other former co-stars Alexis Bledel, 33, and America Ferrera, 30.
Asked if they meet up regularly, she said: "Too often! I just got off the phone with Blake actually. We see each other all the time, all the time, more than I think you guys even know. To like an extreme amount, which I'm always very, very happy with."

Kim Kardashian West feels more confident after posing nude.
The reality TV star has no regrets about baring all in the now infamous photographs for Paper magazine and doesn't think she is setting a bad example for her younger fans.
The 34-year-old star said: "I was so honoured and excited to work with [photographer Jean-Paul Goude] because he is a legend, and for me that was something I wanted to do to make myself feel confident.
"As a role model I'm not saying anyone else should do that, but for me it was an art project and it taught me to do what you want to do.
"I'm never one to preach, but I felt really positive and really good about myself. I love the photos, I did it for me, I hope other people like them."
The 'Keeping Up with the Kardashians' beauty's lower back "hurt for about a week" after she posed with a champagne glass on it for the same spread.
She told Australian TV show 'The Project': "My back hurt for about a week after that shoot...I used muscles. [Goude] has an art of posing you and it was definitely not comfortable."
Kim travelled to Australia without husband Kanye West and their 17-month-old daughter North for a "short trip."
She said: "Last time we spent some time at the Brisbane Zoo and we loved it. My husband took my daughter to the Zoo in Los Angeles yesterday and was calling me saying he missed Australia and how jealous he was that I'm here because the zoos here are amazing. My daughter's obsessed with animals."

Billy Joel respects Taylor Swift.
The 65-year-old singer doesn't understand why the 'Blank Space' hitmaker gets so much abuse from critics because he thinks she is "talented."
The 'Uptown Girl' hitmaker said: "I think she's a talented songwriter. She catches a lot of junk, maybe because she's so popular with young girls. But I like what she's projecting. I respect what she's doing."
Billy, who has lived in Long Island, New York for many years, also blasted city residents for turning their noses when NYC & Company, the city's marketing and tourism organisation, made the 24-year-old singer a tourism ambassador late last month.
The 'New York State of Mind' hitmaker told USA Today newspaper: "You snoots. Let her in. That's what New York is all about. I say, 'Welcome.' "
Taylor bought and moved into a $19.9 million penthouse in Tribeca in the city last March after relocating from Nashville, Tennessee.
The 'Shake It Off' hitmaker previously gushed about her love for the city, saying: "I'm still learning, but I'm so enthusiastic about this city that when I love something, I'm very vocal about it ... It's affected my life in ways I'm not even aware of fully."

Jessica Alba feels like she's constantly being "pulled in 20 different directions."
The 'Sin City' actress, who has daughters, Haven, six, and Honor, three, with husband Cash Warren, says being a mother is her "priority," but it's "impossible" for her to balance them with her acting career and eco-friendly brand, The Honest Company.
The 33-year-old star said: "I feel like I'm pulled in 20 different directions [at all times].
"It can be really long days. When I'm home after I've put the kids to bed I'm still going. When you're running a company there is no nine to five. It's like a 24/7 [job]."
Jessica thinks her daughters are growing up too quickly and is glad Haven isn't ready to move out of her crib yet.
She told PEOPLE.com: "Oh my God, she loves her crib. She wants sleepovers because her sister has sleepovers so I try to do sleepovers with Mom. She says, 'Okay Mommy, I'm done. I need to go back to my crib now.' She's so restless -- she wants to talk so she's super into her crib. It's really cute and I'm like, 'Yes, stay a baby forever.'
"[Being a mom is] my priority. I feel like they're growing up too fast, and I want to freeze them in time. I don't think that's going to happen because every day they're just getting taller and sometimes more sassy."
The brunette beauty admits she wouldn't be able to do it all without a strong support system, including her best friend Kelly Sawyer.
She said: "It really helps to have someone who has your back when we're going through our own trials and tribulations."

Dan Osborne was reportedly arrested after a fight with the mother of his son.
'The Only Way Is Essex' star is said to have rowed with ex-girlfriend Megan Tomlin - with whom he has 11-month-old son Teddy - at her home in Essex before being arrested on suspicion of assault and later released without charge.
A police spokesman told the Daily Mirror newspaper: "A 23-year-old man was arrested at around 11.30am on Monday 10 November. He was later released without charge."
The 23-year-old reality TV star - who revealed earlier this month that it "breaks his heart" every time he has to drop his young son back at Megan's home - is said to be on bad terms with the mother of his child, whom he dated for 18-months before splitting in April 2013.
A friend of Megan's told heat magazine: "Megan is at breaking point. Dan makes out he's the perfect role model, but she thinks he's far from it."
Meanwhile, Dan is now expecting his second child, with his 'EastEnders' actress Jacqueline Jossa - who is set to give birth early next year - despite admitting he's not sure if she is "the one" for him.

Jaden Smith wants to be the "craziest person of all time".
The 16-year-old star - whose parents are Will Smith and Jada Pinkett Smith - has set his sights on being known for achieving some incredible feats when he is older, including becoming the "most durable person on the planet".
He said: "I have a goal to be just the most craziest person of all time. And when I say craziest, I mean, like, I want to do like Olympic-level things. I want to be the most durable person on the planet."
Jaden also admitted he and his younger sister Willow, 14, are inspired to make their own music because they do not like any of the tunes around nowadays.
He said: "Honestly, we're just trying to make music that we think is cool. We don't think a lot of the music out there is that cool. So we make our own music. We don't have any song that we like to listen to on the P.C.H. by any other artist, you know?"
The siblings also share the same beliefs about many other aspects of their lives, and admitted they love to get a reaction out of people by surprising them.
In a joint interview with T magazine when asked what are the things worth having in life, Jaden added: "Anything that you can shock somebody with. The only way to change something is to shock it.
"If you want your muscles to grow, you have to shock them. If you want society to change, you have to shock them."
Willow added: "That's what art is, shocking people. Sometimes shocking yourself."

One Direction are planning to hold Zayn Malik's stag party in Las Vegas.
The 21-year-old pop heartthrob is engaged to Little Mix star Perrie Edwards and his bandmates want to mark his final days as a bachelor by hitting the town in style in Sin City.
When asked where they are planning on hosting his traditional bash, Niall Horan exclaimed: "You know where we're taking you, don't you Zayn ... Vegas!"
Niall's revelation prompted Zayn to say: "Oh no."
Plans for the nuptials are underway, but Zayn has dismissed Perrie's idea to have Disney-themed nuptials.
In an interview with OK! magazine, Zayn said: "Disney?! Oh, I hadn't been told that ... That's probably not going to happen."
Although he is one fifth of the biggest boy band in the world, Zayn doesn't have any intentions to sing at his wedding, but would love to get a famous musician to perform.
He said: "I probably won't be singing. I'd love to have an amazing rock star there. Like Steven Tyler - that would be sick!"
Meanwhile, One Direction are ambassadors for British charity Rays of Sunshine.
The boys - Niall, Zayn, Louis Tomlinson, Liam Payne and Harry Styles - work with the organisation, which aims to grant wishes to seriously and terminally ill children, and are very proud to be associated with it.
Speaking about their work with the charity, the band said: "We love working with Rays of Sunshine. Thank you so much for having us involved over and over again. They do incredible work which we've seen over the last few years and hope to be involved for many years to come."
Rays of Sunshine has just announced a partnership with LaplandUK (www.laplanduk.co.uk) this year to deliver Christmas magic to many children this year through the charity.
LaplandUK - which opens on November 29 on the Windsor Estate - is Britain's leading Santa Claus experience for children, offering families the chance to meet Father Christmas and his Elves at his snow-covered home and will be offering the experience to kids through Rays of Sunshine.
As well as 1D other Rays of Sunshine (www.raysofsunsunshine.org.uk) ambassadors include Olly Murs, Gordon Ramsay and Pixie Lott.