Remember when Lorenzo Lamas, he of Grease, Falcon Crest, and looking-like-Harry-Hamlin fame,  found out that his now ex-wife Shauna Sand (they were married from 1996 to 2002) was sleeping with his then 18-year-old son, A.J., while Shauna was still married to Lorenzo? Oh, memories. Here are a few other ridiculously racy celebrity affairs to ease you into your weekend. 

1. Gloria Grahame cheats on Nicholas Ray with his son
The old nailing-the-father-and-the-son trope goes at least as far back as the director of Rebel Without a Cause and his actress wife. Grahame (who played bad girl Violet Bick in 1946's It's a Wonderful Life) and Ray married in 1948, and had a son, Timothy.

In 1951, Nicholas came home to find Gloria in bed with his 14-year-old son, Tony. They divorced the following year, and in 1960, Grahame married Tony. Together they had two sons. So her oldest, Timothy, was both the half-brother and the uncle of her sons Anthony Jr. and James. Eeeeeesh. 

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2. Elizabeth Taylor steals Eddie Fisher from Debbie Reynolds
There was no one more famous than Elizabeth Taylor in the late '50s. She had been widowed in 1958; the husband she'd loved the most, producer Mike Todd, died when the plane named Lucky Liz, after his wife, crashed.

Todd's best friend, singer Eddie Fisher, comforted Taylor in her grief, and as Eddie's daughter Carrie writes in her screamingly funny book Wishful Drinking, "He first dried her eyes with his handkerchief, then he consoled her with flowers, and he ultimately consoled her with his penis."

Debbie Reynolds became the Jennifer Aniston of mid-century Hollywood, with outraged fans taking her side versus that trollop Elizabeth. Liz and Eddie were married in 1959, and split in 1964, when she dumped him for Richard Burton. Debbie and Liz, who had been close friends, reconciled years later and even mocked Fisher in the 2001 TV movie These Old Broads, which Carrie Fisher wrote.

3. Meg Ryan throws Dennis Quaid over for Russell Crowe
Meg and Dennis were a golden couple: He gave up coke for her, they married in 1991, and had a son, Jack, the next year.

All was peachy (except for the occasional rumor of Dennis catting around), until Meg went to Ecuador to shoot Proof of Life in 2000. She and costar Russell Crowe, then separated from his longtime girlfriend and future wife Danielle Spencer, began an affair that hastened the end of her marriage to Quaid and sullied her girl-next-door image.

4. Notorious B.I.G. sneaks around with Lil' Kim behind Faith Evans's back
Biggie Smalls, né Christopher Wallace, packed a lot of living into his 24 years. He married singer Faith Evans in 1994, just before his first album, Ready to Die, was released. In October 1996, Evans gave birth to their son and Lil' Kim, Biggie's protégée, released her first album, Hard Core.

Two months later, Evans caught them in bed together, as she writes in her book Keeping the Faith: A Memoir: "As soon as I saw a small lump next to Big's large frame, I flew into a rage … I grabbed some chick out of the bed and started beating her ass. At some point, the chick's wig came off in my hand: It was a short, cropped wig. I stopped throwing punches for a minute to get a good look at the chick I was beating up. It was Lil' Kim."

Wallace was killed in a drive-by shooting less than three months later, and Faith and Kim eventually came to have a civil relationship.

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5. Mick Jagger knocks up a Brazilian model while married to Jerry Hall
Mick left his first wife, Bianca, for 22-year-old model Jerry in 1978; they had a son and daughter before marrying in 1990, then two more children, the last born in 1997. Less than a year and a half later, tabloids began reporting that Mick had gotten Luciana Morad, a 28-year-old Brazilian catwalker, pregnant.

People also reported that just after Hall gave birth to their third child, in 1992, Mick was in Thailand shagging Carla Bruni, now the first lady of France. But Luciana's pregnancy was the last straw for Jerry, who filed for divorce only to find that their Hindu wedding on Bali was not legal.

The marriage was annulled in 1999, with Jerry getting a settlement in the neighborhood of $10-15 million. Mick didn't marry his latest model. 

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Sara Brady is a freelance writer and editor living in Manhattan. 

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