For months, rumors have circulated that Casey Aldridge has cheated on Jamie Lynn — but no one has come forward to confirm them, until now. In an exclusive interview with In Touch, 28-year-old Kelli Dawson reveals that she and Casey, 19, were romantically involved — and were still sleeping together when Jamie Lynn, now 17, was six months pregnant with his child.

The pair didn’t bother to hide their relationship. “Kelli and Casey have been a couple on and off for a few years,” confirms Jason Alexander, Britney Spears’ first husband and a native of nearby Kentwood, La. “They were a really tight couple, but I think it was hard for Kelli, having Jamie Lynn in the picture.”

Britney's first, daylong husband? Now that's sourcing! In the face of this incontrovertible evidence, Jamie Lynn would be well advised to take a page from her mother's Guide to Fucking Up Your Children (specifically, Page 119): "Now that the first potential husband is dispensed with, enjoy a wider pool of adventures that involves paparazzi, backup dancers, and Cheeto-covered, high-thread-count sheets."

• Jamie Lynn Spears is betrayed [InTouch]

Star
Jamie Lynn's "baby joy turns to tears…" because her shotgun wedding to Casey Aldridge is allegedly off! Despite frequent, happy looking trips to Wal-Mart, the two teens fight all the time. Even worse, Casey is reportedly two-timing Jamie Lynn! "Casey is acting like a dog," a local yokel notes. And Casey's not the only "celebrity" behaving badly. The Hills Whitney Port is acting like a diva, showing up late to appearances and demanding trips to 7-Eleven. Even more shocking: a Whitney Port personal appearance commands $14,000. New moms Melissa Joan Hart and Jaime Pressly are gabbing about their new baby boys. Jaime ate cabbage soup six days a week and worked out two hours a day to lose her baby weight. Sounds…farty and ill-advised. Lilo hates Mary-Kate Olsen because of her friendship with Samantha Ronson, although MK is really scared of people thinking she's a lezebel. John Mayer has a touch of the OCD: since moving in with Jennifer Aniston at her hotel in Florida while she shoots Marley and Me, he has been cleaning up after her cleaning lady. Jen, who is 9 years older than John, is also featured in a spread called "Cougar Season" alongside Mariah, Ellen DeGeneres, and ur-Cougar Demi Moore. Ladies sometimes date younger men: this is not news. We are officially over the term "cougar."
Grade: D (falling asleep outside and having someone write "Dick" on your stomach in sunblock)
Us
Former jilted Bachelor star Andrew Firestone has a "Second Chance At Love," the Us cover blares. Even though ex-fiancée Jen Schefft dumped him on his keister after the show aired, Firestone has found love with a leggy blonde Serbian model named Ivana Bozilovic. You guys, it's so hard to rebound from a break-up when you're a ridiculously good-looking heir to a tire fortune. Firestone has been through so much! Not as much as breakup postergirl Jennifer Aniston. But things seem to be looking up for our formerly depressed diva! Her friends all love new boyfriend John Mayer, even notoriously tough Courteney Cox. Several preggers stars are just about ready to "pop": Gwen Stefani, Nicole Kidman, Jamie Lynn Spears, Luciana Damon (Matt's wife) and Ryan Shawhughes (Ethan Hawke's gf) are among the super pregs. Patrick Swayze has gone back to work on the forthcoming A&E series The Beast even though he was diagnosed with pancreatic cancer. No cancer puts Patrick in a corner! Kim Cattrall signed on to executive produce and star in a new HBO comedy, Sensitive Skin, which is about a woman rediscovering her sexuality. "Even though it's my name, and the word skin is there, it's a very subtle show," she assures Us. Mmmkay.
Grade: D- (subway smells on a 99 degree day)
In Touch
Angelina is "Pushing Brad Away!" Nooooes! Apparently Ange has violent mood swings because of all the pregnancy hormones and Brad can't deal with it. He took Maddox to the MotoGP motorcycling championship just to get the eff away from Angie. At least she's not back to her Billy Bob humping days, but allegedly Nicole Richie is back to her old bad habits, namely not eating. She's down to 95 pounds, only ten pounds heavier than her scary looking lowest point. Also back to bad habits: Brit Brit. She's back on the sauce, but still not doing drugs, though some fear that Britney's cocktail swilling might lead back down the road to cocaine corner. Also: there's some sidebar saying that Britney's boozing is causing her to have acne. WTF? Did a boob job come between George Clooney and Sarah Larson? Apparently Larson got her tatas done in May, and George wasn't happy about it. Sarah, however, is so thrilled with her new bod that she is considering posing for Playboy. Sigh.
Grade: F+ (second degree sunburn)
OK!
Aw, Shiloh is excited about Angelina's new babies! Apparently SO excited that OK! felt the need to devote four pages to the minutia of Shiloh's very existence. She has "pull-up diapers and tells Mom and Dad when she has to go to the bathroom"! She is learning to sleep alone! She puts her hands on Angie's stomach to feel the twins kick! Um, just like ANY OTHER TWO-YEAR-OLD EVER IN THE HISTORY OF LIFE. Brad Pitt might be making babies these days, but according to a "friend" of John Mayer's, Brad doesn't stack up to John in the sack. John is "Not just good, but sensational" at the sex." Jen is so appreciative that she's started glowing and wearing dresses. Or something like that. Mutiny in The Hills! Lauren Conrad and Audrina Patridge are brawling. There's a photo shoot with Audrina at her pool house, behind the main house where Lauren and Lo live, and apparently L.C. was pissed about it. "She was very, very mad." Audrina says. "She said it's her house. But this is my room…No she thinks I'm sneaky and shady for doing this photo shoot, yet she and her team knew about it." Dramz!
Grade: F (boob sweat on a date)
Life & Style
Katie is Tom's Prisoner. Again. Katie went to New York for four days to rehearse for her new play, All My Sons, and she never went anywhere but the hotel and the theater. She looked annoyed at a party, according to an "insider" and it's because she feels suffocated. Is John Mayer ready to be a dad? Life & Style ponders. Jen started talking about a friend's fertility treatment over dinner and John "swiftly" changed the subject. "This spinach is awesome…It's very garlicky," Mayer reportedly said. Heh. Maybe that's why Jennifer Aniston has been feuding with He's Just Not That Into You co-star, Jennifer Connelly. The cast of the film, which includes Drew Barrymore and Ginnifer Goodwin, got together for a Marie Claire photoshoot, and Aniston threatened to pull out if Connelly was included. Janet Jackson looks to be "up 20 pounds" since October, and she needs to lose weight before her Rock Wichu tour in September. She plans to eat healthier and exercise more and blah blah blah.

Grade: F- (heatstroke)

As MSNBC reports via OK!, Jamie Lynn is gonna be a single mom for a while, having decided to wait until after she gives birth and sheds the preggers weight before tying the knot. As the magazine's source says, "I expect she'll want to wait at least several months to get her figure back so she can wear a beautiful wedding gown and then have her dream wedding." What else will that "dream wedding" include? Big sis Britney as bridesmaid. We just hope she remembers to show up sober (and sans donning ripped denim) for this one.

[Photo Credit: X17]

• JAMIE LYNN IS ALREADY PLANNING HER WEDDING [MSNBC]