Teen star Demi Lovato, Ryan Phillipe romance in trouble

Updated: Jul 20, 2011, 12:18 PM IST

Los Angeles: Demi Lovato has reportedly been dating actor Ryan Phillipe, but things have taken a back seat after it was alleged that he is the father of his ex-girlfriend Alexis Knapp`s newborn.

The 18-year-old singer-actress was not aware that Phillipe was going to become a father for the third time, according to sources.

The actor already has two children, Ava Elizabeth, 11, and Deacon Reese, seven, with ex-wife Reese Witherspoon, reported E! Online.

"It was really hot and heavy for a while, until it basically happened. It kind of threw her for a loop," a source said.

The `Stop-Loss` actor stood by Knapp during her labour, although it is yet to be confirmed whether he is the father and is waiting for results of the paternity test.

"He is a good father, and whether this is his baby or not, he wants to do the right thing and be supportive," a source said.

Phillipe is also said to have had an on/off relationship with actress Amanda Seyfried earlier this year.