LOHAN LUNACY - LINDSAY LOHAN GAINS A HALF SISTER: LINDSAY LOHAN'S dysfunctional family has grown by one. Michael Lohan has denied for years that he fathered a lovechild back in 1995, and today on the syndicated “Trisha Goddard” talk show he will take a DNA paternity test to prove once and for all one way or the other.

Spoiler alert! He IS the father. Lindsay, it turns out, has a 17-year-old half-sister she never knew about. Her name is Ashley Horn, and for years her mother Kristi has tried to gain child support from Lohan, but he's always refused citing proof of paternity as the reason. Maybe now he’ll change his tune. Or not. This is Michael Lohan we're talking about, after all.

BON JOVI’S DAUGHTER ARRESTED FOR HEROIN POSSESSION: JON BON JOVI got shot through the heart yesterday ... metaphorically speaking, that is. His 19-year-old daughter was arrested in upstate New York yesterday morning after allegedly overdosing on heroin. TMZ reports that cops and medical emergency personnel were called to Stephanie Rose Bongiovi’s Hamilton College dorm room after she was found unresponsive.

During a search of her room, cops found a “small quantity” of heroin and marijuana, as well as other drug paraphernalia. She was arrested for possession of a controlled substance, possession of marijuana and criminally using drug paraphernalia - all misdemeanor charges.

RIHANNA TALKS TO ELLEN ABOUT HER DATING LIFE: When RIHANNA appeared on the "Ellen DeGeneres Show" a year ago, she told Ellen she wasn't dating anyone at the time and not only was she not happy about it, a body part she referred to as "her" wasn't either. Fast forward to RiRi's return visit yesterday. The always inquisitive Ellen asked about the status of Rih's body part, and apparently, it's been a good run for "her" lately. Watch!

On a related note ... Madame Tussauds in Las Vegas and Los Angeles just unveiled their new wax figures of RiRi, pictured here below.

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BABY POOP - ELIZABETH BANKS WELCOMES SECOND SON: ELIZABETH BANKS is a mom again. Banks hit up her website yesterday to announce that she and husband Max Handelman are excited to welcome their second son into the family. A boy they named Magnus Mitchell Handelman. The couple’s first child, Felix, was born last year. Both were born via gestational surrogate.

MARIAH CAREY IS A DIAPER DIVA: It’s no secret MARIAH CAREY is a diva, just ask NICKI MINAJ, so it’s no surprise to hear she doesn't like handling the dirty work involved in parenting. Mariah’s hubby NICK CANNON revealed on "Anderson Live" earlier this week that he’s the one usually stuck changing their twins’ dirty diapers. “I mean we all do it but for some reason I get the duty a little bit more," he tells Anderson, adding, "I am not scared of it. I go in, I put the gloves on!”

Mariah, by the way ... will join CEE LO GREEN, ROD STEWART, and TRACE ADKINS among others on the 15th annual Christmas in Rockefeller Center special, airing November 28 on NBC.