• Alessandra Ambrosio just gave birth, but she isn't wasting any time. She's reportedly already looking to sell pictures of her newborn daughter Anja to the tabloids. [P6]

Last week's debut of Defamer Answers seemed to go reasonably well, with our survey of the phenomenon that is The Jonas Brothers provoking rich discussion among fans, enemies and baffled cultural observers alike. This week's edition finds us contemplating a far less-heated subject whose profile is surging nevertheless: Courtenay Semel, an entertainment industry scion and B-list lesbian whose exploits have landed her everywhere from reality TV to the interior of Lindsay Lohan's pants over the last three years. But her recent detention in Vegas after a drunken, assaultive visit to Caesar's Palace is what really compelled our consideration here: Who is this Hebrew hellcat, anyway? After the jump, learn everything worth knowing about Semel's climb to sort-of fame.I. KNOW YOUR SEMELS Courtenay, 28, is one of three daughters born to billionaire ex-Warner Bros/Yahoo! chief Terry Semel and Jane Bovingdon Semel, a former secretary to Susan George. She attended the Loomis Chaffee School in Windsor, Conn., before abandoning education for... we don't know. This is a historical gap we have yet to fill in; suggestions are welcome. Regardless, she's clearly been doing some philosophizing over the decades, culminating in the powerful declaration of principles held forth below: II. KNOW HER CANON Courtenay got her start in 1991, portraying the crucial role of "Bratty Kid" in the Bruce Willis flop Hudson Hawk. Her 2000 follow-up — the never-released indie thriller Sweetie Pie — is best known for a cast also including Paris Hilton, Whitestarr vocalist Cisco Adler and the offspring of Dustin Hoffman and Kelsey Grammer. Her "break" (and all of ours, really, if we're being honest) came when she was cast alongside childhood friend Kourtney Kardashian, George Foreman III, Fabian Basabe, Brittny Gastineau, Shanna Ferrigno and other nepotism all-stars on the 2005 E! series Filthy Rich: Cattle Drive. The show featured Courtenay and Co. skipping the boilerplate South Beach coke getaways for a bit of reality-TV ranch-handery. Sadly, due in part to reasons listed below, it was not renewed for a second season. III. KNOW HER ACCOLADES Courtenay's otherworldly bitchy contribution to FR:CD was roundly commended by critics who cited her distinctive look ("like an overfed mutant chipmunk") and her performance as a "brattier, PMS’ing version of Haley Joel Osmond [sic]" — outmaneuvering even Basabe as the worst human being the show had to offer. Word is her father was happy with the performance in Hudson Hawk as well, but as of press time he has not responded to Defamer's requests for official comment. IV. KNOW HER STYLE Spoiled lipstick-lesbian chic, at once aggressively designed and thoroughly disposable — all spangles, trash, heels and hair.

Hollywood C-list scenester Courtenay Semel — former Yahoo CEO Terry Semel's daughter — left Pure nightclub last night with her MySpace and MTV famous girlfriend, the pseudo-bi Tila Tequila. Then she "smacked" a security guard in the back of the head. Security detained Semel until police arrived four hours later and issued her a citation for battery. Where was this kind of feistiness in papa Semel when Google started stomping all over Yahoo?(Photo by Getty)

• Courtenay Semel, daughter of former Yahoo CEO Terry Semel, spent the night in jail after a night of carousing with her semi-girlfriend Tila Tequila and with Kourtney Kardashian. Semel apparently got into a fight with a security guard from Pure in Caesar's Palace, because what is there to do, other than be ANGRY at the world and at an underpaid hotel staffer, when you're a billionaire's daughter, on vacation in Las Vegas, leaving a glitzy nightclub with your smoking hot lesbian girlfriend? [P6]

• Matt Damon's wife Luciana gave birth to the couple's second child together yesterday, a girl named Gia Zavala Damon. [NYDN]

Congratulations are in order for Ellen DeGeneres and Portia de Rossi, who married Saturday night in an intimate ceremony held on the grounds of their California home. The brides both wore Zac Posen and exchanged handwritten vows promising to love each other "in sickness and in health, for as long as no pesky cameramen get in the way." Attendance was capped at 19, all the better to exclude potential wedding crasher Barbara Walters. Still, the lesbian goddess giveth with one hand while she takes away with the other, for no sooner did the two marry than details of a sapphic Hollywood breakup emerged involving the famously "gone gay" Lindsay Lohan.

• Ellen DeGeneres and Portia De Rossi officially tied the knot in front of 20 guests at their Beverly Hills home on Saturday, exchanging handwritten vows and Neil Lane rings. Ellen wore a pants suit; De Rossi opted for a Zac Posen gown. [NYP]

So remember how heiress Courtenay Semel made out with reality TV star Tila Tequila in a bar recently, and famous lesbian couple Lindsay Lohan and Samantha Ronson sat there laughing at them the whole time? No?? Your loss. Anyway, the whole thing is sort of funny in retrospect, because it turns out Lohan dated Semel before she famously edged out of the closet recently with public displays of affection for Ronson. And Ronson kind of stole Lohan away, according to a salacious British tabloid report:

Plasticly popular MySpace personality Tila Tequila and Courtenay Semel, the daughter of ex-Yahoo CEO Terry Semel, attended a premiere together last night in Los Angeles. There, the pair confirmed a more successful merger than Semel senior ever managed. “I’d seen the show [A Shot at Love] and just needed to meet her and it just happened,” Semel told People magazine. “It’s true what they say about lesbians," said Tequila. "You meet and then the next day you move in together, because I can’t get rid of her. She pretty much lives at my house.” We think this is the only Yahoo-MySpace deal we'll see happen. (Photo by AP/Steinberg)

• Sad Tori Spelling is un-joining the 90210 spinoff because she's making like half as much as Shannen Doherty. Which is unfair because Spelling wrote a bestseller! Wait, really? (Yes. Sigh.) [Deadline Hollywood]

• Courtenay Semel, lesbian daughter of Yahoo's CEO was dating heiress Casey Johnson until a drunken hookup with Tila Tequila at some party. Lindsay Lohan and Samantha Ronson totally giggled. [P6]

• Caleigh Perelman is still refusing to talk to her mom Pat Duff, or even go on vacation with her. Now a judge is warning Ron Perelman not to interfere with their phone calls and visits. He also ordered Caleigh to undergo a psychological evaluation before the couple return to court next month. [NYDN]

• Did Uma Thurman and Arki Busson get secretly married during their engagement party earlier this month? If so, does that mean the European vacation they're on right now is really a honeymoon? [Page Six]

• It's two days since Knox Leon and Vivienne Marcheline Jolie-Pitt were welcomed into the world by Brad and Angelina and it's been just as low-key as everyone expected. The mayor of Nice, Christian Estrosi, signed the birth certificate at a press conference; now the discussion has turned to pics of the babies, which are expected to fetch $15 to $20 million. [People, NYDN]

• The daughter of former Yahoo CEO Terry Semel, Courtenay, is dating the heiress to the Johnson & Johnson fortune, Casey. Semel used to date Lindsay Lohan, Johnson used to date a dude, until he was "snatched" away by her aunt. [P6]

• Heiress Casey Johnson and Courtenay Semel, daughter of entertainment mogul Terry Semel, are officially dating. Casey is ditching plans to move home to Manhattan so she can stay closer to Courtenay in LA. [Page Six]

The New York Post likes to run "blind items" — a gossip-column tradition where just enough details are given to help readers guess who's being talked about. Here's the latest: