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The Papa and the daughter

Fasten your seatbelts; it's going to be a bumpy column. The world moans, "TMI!" but we at SideShow depend on stuff like the new Mackenzie Phillips memoir, High on Arrival. She told her story yesterday to Oprah. A daughter of "Papa" John Phillips of the Mamas and the Papas, Mackenzie says she and dad had an affair for 10 years. It began in 1979, when she, then 19, was about to marry Jeff Sessler, a Rolling Stones entourage guy. Papa swooped in to stop it, everybody got upset, got wasted, and . . . well . . . . The next year, Mackenzie was fired from her role as Julie on CBS' One Day at a Time, a casualty of the drug addictions with which she has struggled ever since. Mackenzie's half-sister, singer Chynna Phillips, tells Us mag that when she first learned of the affair, in 1997, "Somebody could have dropped a piano on my head and I probably wouldn't have felt it. But I knew it was true." John Phillips died in 2001. Normal is easier to keep straight

As for uncapitalized mamas and papas, Sarah Michelle Gellar and Freddie Prinze Jr. welcomed their first child Saturday. Hey there, Charlotte Grace! Buffy the Vampire Slayer alumnae have been fertile this year: Alyson Hannigan had a child with hubmeister Alexis Denisof. Just watch those kids when the full moon's out . . . .

A few miles on the Odom-meter

Now speak, muse, of baby mamas.

If you live on Earth, you know that Khlo Kardashian is marrying Los Angeles Lakers' ball-bouncer Lamar Odom on Sunday.

Two years ago, he split up with one Liza Morales, mother of their three children, one of whom died of SIDS. He and she were together about 10 years and have no formal custody arrangement. Morales, who learned of the fast-track wedding in an e-mail, says, "I thought it was a joke."

Well, that's OK, Liza, you still can. You can also say a few things that might worry Kardashian, such as that Odom was "a commitment-phobe" (Morales accepted a proposal from him eight years ago, but, like, well, see, they never like got around to nothing) and that these days they "really don't hear from him too much." Nice!