filed under: Justin Timberlake

If there's one thing we can count on from Madonna, it's the making of a little music history now and again.

Britney Spears and Justin Timberlake will be performing alongside the Material Girl Thursday when her Sticky & Sweet tour touches down at Dodger Stadium, E! News' Ryan Seacrest has learned.

"They are going to be onstage performing with Madonna," Seacrest said on KIIS-FM host DJ BoyToy Jesse's Wednesday-afternoon show.

Of course, while Timberlake and Spears have both collaborated with Madge individually, the exes haven't been spending much quality time together in recent years.

"If Justin and Britney end up on that stage with her...I don't know if I've ever seen anything quite like that before," Seacrest said. (And he's seen a lot—remember Celine Dion performing with hologram Elvis on American Idol?)

Seacrest said that he should have more details on his KIIS morning show tomorrow: "Expect some real serious surprises."

"Jessica is under a lot of pressure to stay in shape because there is so much competition among young actresses in Hollywood. Jessica loves to work out and so does Justin, but lately it seems like that's all she does. She's got an amazing body and Justin is trying to get through to her that she can afford to take some time out once in a while and have a burger, some beers and a day doing nothing."

Justin Timberlake has been shopping for an engagement ring.

The singer is planning to propose to Jessica Biel and is asking her close friends to help him choose the perfect diamond band. A pal of Jessica's told the Chicago Sun Times newspaper: "Justin has been ring shopping, and we're talking serious, major Harry Winston-type shopping here. He has been quizzing Jessica's closest pals and associates, trying to get a take on the kind of engagement rings she has admired. The only comment I ever heard Jessica make was when she complimented a mutual friend's square-cut emerald ring - when a girlfriend of ours got engaged. It was huge!"

Justin's friends claim the 'SexyBack' singer realised he wanted to take his relationship with Jessica to the next level after their busy work schedules kept them apart for long periods.

Last month, it was claimed Justin was ready to marry Jessica on the privately owned island of Mustique in the West Indies. A source said: "Justin is 27 and thinking about marriage and kids. For the first time in his life he is feeling settled and has definitely decided to pop the question to Jessica."

For the last six weeks, Britney Spears has essentially been grounded by her daddy, Jamie Spears, in a desperate measure to save her life. Of course, there are worse places to be holed up than her $7.2 million, 7,400-square-foot Mediterranean-style villa in Studio City.

As part of her dad's restrictions, the 26-year-old is no longer allowed to hit the night clubs in L.A., hang out with her paparazzi pals or make frequent, erratic stops at gas stations, fast-food joints and public bathrooms. A friend of the the singer tells OK! that Brit recently snuck a text message to them saying, "I'm so bored. I hate my life."

Now, a typical day with Britney includes spending hours alone in her bedroom, which a frequent visitor to the home tells OK! is "like a princess' room with several walk-in closets and a spa tub, plus a long counter where she used to keep all her wigs."

Jamie, who stays in a room downstairs, leaves his daughter alone when she's in her private suite. And since she's no longer allowed to go out, the pop star now spends hours in front of the mirror trying on different outfits.

"Changing clothes all day long must seem harmless enough, so her dad doesn't interfere with that," a friend of Britney explains to OK!. "She'll change three or four times on days when she's not leaving the house."

Some of those clothes include "fat clothes" that Britney likes to wear when she's feeling bloated or out of shape. Friends say the singer keeps a secret closet stocked with these loose-fitting garments for just these occasions.

One thing visitors to Britney's home are surprised to discover is that the seemingly scatterbrained star keeps a clean house. "Her life may seem out of control, but the inside of her house is very ordered," a friend of the singer tells OK!. "She's very clean and has no clutter."

An even bigger surprise inside the house — a shrine to ex boyfriend, Justin Timberlake!

Sources tell OK! that few people have seen Brit's collection of private mementos from her years with the pop superstar. "She's obsessed with him," the source reveals. "She has pictures of them together and has devoted a private area just to celebrate him."

"The world has always been full of Madonna wannabes and I might have even dated a couple . . . She has still found time to kiss someone I may or may not have publicly kissed myself while I was in the audience. Of course you know I was talking about Sean Penn."

She gleefully recalled when she met her long-time publicist Liz Rosenberg. She was "smoking a joint,” Madonna said. She also told the crowd she split a tab of ecstasy with a music executive who she gave her first demo tape to.

"Justin was really taking his time looking round the rings. He made the staff get a couple out of the cabinets so he could properly look at them. He didn't buy anything but told the manager he would think about it."

Britney Spears made a name for herself as a happy, wholesome pop star who was saving herself for marriage.

But lawyer Eric Ervin, who worked with Spears as a teenager, tells Us Weekly in its new cover story that the "virgin" image Spears portrayed was, in his words, a "PR blitz." In fact, Us reports in its new issue that Spears lost her virginity at 14 to boyfriend Reg Jones, and that she and Justin Timberlake were intimate from the beginning.

Something Spears also kept secret: Her family's tragic history.

Us has learned that Spears' paternal grandmother, Emma Jean Spears, in June 1966 committed suicide at age 31. Britney's grandmother, who suffered from depression, shot herself in the chest with a shotgun at the grave of her infant son who had died eight years earlier just three days after being born.

A local newspaper article obtained by Us reported at the time: "The shotgun had been pressed against the woman's chest and she apparently pulled the trigger with a toe of the right foot from which a shoe had been removed." The newspaper reported that Emma Jean had attempted suicide three times before.

Emma Jean Spears left behind four other children, including Britney's father, Jamie Spears, then an eighth grader. Two of Jamie Spears' brothers ended up with criminal records and homeless.

Britney Spears is on the offensive in her ongoing battle with Fed-Ex. We're told the popwreck wants to prove she's not the only one who screws up.

Sources tell TMZ Brit has hired a P.I. company to dig up dirt on her ex. One source says, during their marriage, Spears witnessed K-Fed smoking dope and drinking beer around the kids. Brit's camp hopes they can get the goods and turn the tables in the custody battle.

"He phoned Evolution Surf and ordered a longboard with a blue, yellow and gold design. He also put in an order for a year's supply of Sex Wax. He thought it'd be fun to surprise her with a board and a trip to Hawaii to teach her how to surf!"

"It looked like the friend reached over and squeezed Jessica’s butt while Justin was looking out at the field. Jessica didn’t even flinch - but when Justin suddenly turned around, Jessica’s friend pulled her hand away."

Britney Spears backed out at the last minute from recording a duet with her old flame, Justin Timberlake - and the inexplicable decision last month has suits at her record label, Jive, very worried.

The duet, which was to be produced by hit-maker Timbaland at his studio in Virginia Beach, could have started a big comeback for the troubled pop tart, who peaked before she had two marriages and two kids.

A music industry source said Timberlake wrote the duet specifically for Spears. Although they wouldn't be together in the studio, his voice would have been mixed with hers later.

"Timbaland set aside a week out of his crazy schedule to do this - and then, just before she was supposed to fly out, Britney abruptly canceled the session and refused to do the song.

"It's crazy," the insider added. "She's looking for a comeback, and this would have not only been a huge hit, but something she could have opened the MTV Video Awards with and really blown everyone away."

Another insider said, "Listen, everyone is worried. In her mind, her album is done and she's done enough work . . . She's an easy target right now, because she's . . . sick. People like her are sick. It's like an anorexic who's sick in the head and needs help. She needs help. It's sad because what she's got - and we've heard it's like bipolar disorder - can easily be treated with medication, but she won't do it."

There's concern that Spears, now without a great song to perform, will bomb at the VMAs, which would have been her crucial comeback appearance.

As for whether or not Jive has wiped their hands of Spears, the insider said, "People at Jive have been with Britney since album one, and have an investment in her. They have faith that once the material is there, she will become focused and step it up. She's very competitive, but at the end of the day, it's hard. She has to do the work - no one can do it for her."

Reps for Jive and Timberlake declined to comment. Spears, who's embroiled in a nasty custody battle for her children, Sean Preston and Jaden James, with her ex-husband, Kevin Federline, doesn't have representation and couldn't be reached.

Biel, 25, arrived in Amsterdam Sunday evening, and she and Timberlake, 26, holed up in The Dylan, a romantic five-star hotel.

On Monday, they arrived in Stockholm. That evening, the pair - with a 13-member entourage - ate at Stockholm's Beirut Cafι, a Lebanese restaurant. "They seemed like an ordinary couple in love," owner Elias Karroum tells PEOPLE. "They were very sweet."

Adds Karroum: "They also tried to smoke a water pipe with apple-flavored tobacco. They said they'd tried it before, but we had to show them how to do it properly."

"She truly insisted that she came with me on tour. I don't know how to say no to a pretty face. But it wasn't really a good idea. This time I'm putting the machine before everything else. Jessica met up with me in Manchester, but for Paris I told her categorically no. This tour is very important for me. I'm doing it really seriously so there's no question of playing sweethearts."

"I met Justin Timberlake and I liked him. I met his mother too. He brings her on tour with him, I guess as some sort of prop. When we met I had just watched this sex documentary, unfortunately for his mother, and the first thing I said to her was 'Did you know that a woman has three holes between their legs?' She was fascinated."

Justin Timberlake's fans have been told they can "touch" but not "grab" the singer.

The singer's security team reportedly laid down the strict instructions to people in the front row of his 'FutureSex/LoveSounds' tour.

A source said: "They were quite specific about what was and what was not allowed. We've never known anything like it. It was hysterical."