The romance between Heroes co-stars Hayden Panettiere and Milo Ventimiglia is reportedly already moving to the next level - with Milo integrating himself with her family.

The pair denied romance rumours last autumn but last week Milo was reportedly overheard telling friends he considers Hayden to be his girlfriend and he’s in love with her.

A source close to the Hayden’s family added that the feeling is mutual and the 18 year old actress has introduced Milo to all the important people in her life: “Hayden’s mom adores Milo. She thinks he’s so cute. She tells her friends that he’s her boyfriend. She’s very proud.”

“He’s even met her grandparents. He fits in perfectly with the family. Milo jokes around with her little brother. They’re buddies.”

The source added that the couple seem well suited: “they’re very affectionate and very comfortable around each other. He really takes care of her, even down to the little things like giving her a back massage and going with her to work things.”

But the 12 year age gap between the two is evident sometimes: “At first it doesn’t seem like there’s a big age difference, but then you do see it. … He’s more proper and reserved, and she’s still playful and very girly.”