Looks like Milo Ventimiglia and Hayden Panettiere are going back to being just uncle and niece.

After more than a year together off-screen, the Heroes stars have officially called it quits. (Did someone have a wake up call?) Insiders claim the split was a result of two people simply being in different stages of their lives.

News of their relationship initially raised eyebrows because of their 12-year age gap. Milo is 31; Hayden turned 19 back in August. The two were first spotted together in late 2007, shortly after Panettiere’s 18th birthday.

According to a People source, the pairing never seemed entirely steady. “She still has growing up to do and he’s very low-key,” they explained. “She likes to go out in the Hollywood scene and that’s not his style,” an Us Weekly source added.

And though age most likely played a factor in the breakup, was that the only reason? The Chicago Sun-Times says maybe not. Rumor has it someone may have had to purchase a home pregnancy test. Although the results were negative, the fallout lead to the eventual split.

I think a trip back in time would probably come in handy right now….