Lohan Clan Blindsided By Michael's Paternity News

After years of public denial, Michael Lohan has finally proven to be the father of 17-year-old Ashley Horn after taking a paternity test on the Trisha Goddard show. Now, Dina Lohan is speaking to ET about how she was blindsided by the news.

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"Years went by and we had no idea," said Dina. "And the woman actually called me -- the mother of the child -- crying and apologized to me. It was so long ago that ... I mean, it's not the child's fault obviously, she's just a product of that."

As Ashley was born in 1995, Michael would have still been married to Dina at the time of her birth.

In a 2008 interview with ET, Horn revealed letters she received from Michael while he was behind bars, implying that he was her dad. At the time, he still upheld the public stance that he hadn't fathered her.

Lindsay Lohan supposedly hadn't heard about her father's paternity test and half-sister until she appeared live on Good Morning America on Friday.

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Watch the clip for more.