Exclusive: Larry Birkhead, Anna Nicole's Ex, Speaks Out

Aug. 30, 2010— -- An ex-boyfriend of Anna Nicole Smith said he feared for his unborn daughter's safety when Smith appeared impaired while pregnant before her own death by overdose three years ago.

"Until I got my daughter back, I worried every single day," Larry Birkhead told "Good Morning America" in an exclusive interview, referring to the time after the couple's daughter, Danielynn, was born.

"But once I got her back and took her to the doctors and took her to all these different specialists to make sure everything is OK, they all assured me, 'Your daughter's healthy, she's happy.'... I got lucky."

Birkhead is a witness in the ongoing trial of another of Smith's former boyfriends and lawyer, Howard K. Stern, as well as two doctors who are accused of illegally supplying Smith with drugs.

The reality star and former Playboy model was found dead of a prescription drug overdose in February 2007.

Birkhead said he believes the charges against Stern, in particular, are "unfair."

"Howard's being held, in my opinion, to the same standards as the doctors, almost as if he prescribed the medications," Birkhead said.

It's hardly the first time Birkhead has been in court because of a Smith-related controversy. He came out the winner in 2007 in a whirlwind paternity case that also involved Stern.

While the trial was nothing short of a tabloid frenzy, Birkhead told "GMA," he was so confident he was the girl's father that he promised Smith he would care for Danielynn, who turns 4-years-old in two weeks.

"We all got to put something in the casket, and I put a three-page letter -- this is before the DNA test -- saying I was going to take care of Dannielynn," he said. "That's how certain I was that she was mine, and the charade was over. I just told her that she was going to be fine."

Birkhead is teaching his daughter her ABC's but, he said, worries about other things she might learn, such as about the uglier side to her Playboy-model mother's life.

"If her Mom comes on television, she will say that's her mom, that's Anna Nicole," Birkhead said. "I think that I do worry that kids in school might say something ... and some of those things could be cruel at times.

"I just hope that I get the opportunity to explain some of the things before she gets to the point to where people come and tell her," he added. "There's so many [things] that I have to worry about telling her. She's running but I'm still taking baby steps."