"Oh, come on, stop with the fake tears!" he says, in our all-new interview. "If Ashley and even Kristi want the limelight and they want to be actresses ... they better start taking some acting lessons."
All week long, we've been bringing you interviews with the mother-daughter duo, including the letters signed "Love, Daddy," Ashley says Michael wrote to her from prison, and her pleas to meet with his other daughters, Lindsay and Ali Lohan.
"She actually had me believing I was the daddy," he tells "The Insider. "I actually put that in the letters. I said, 'Call me daddy' -- that's how much I believed it."
It all began years ago Kristi says, when she had a three- to four-week affair with Michael.
"When he came back, I told him I was pregnant," she says. "I knew he wasn't happy about it so I gave him the door ..."
Michael is currently taking a DNA test to determine paternity, but he says he has information that leads him to believe he may not be Ashley's father: "After what I've read and what I've heard and what I've found out -- there's a chance I'm not!"
Don't miss tonight's "Insider" for more on Michael Lohan's all-new interview!
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