There’s a lot of controversy over the relationship between Heroes co-stars Hayden Panettiere, 18, and Milo Ventimiglia, 30. Some people say she’s of age and they’re a nice couple while others find it creepy that a 30 year-old man would date someone over 10 years younger. He’s not admitting much to the press, though, and recently called himself single in an interview with Cosmopolitan Magazine.

34 year-old Grey’s Anatomy star T.R. Knight has a new boyfriend, and he’s a college co-ed who’s just 19 years old. That’s more of an age difference than Milo and Hayden. T.R. and his new beau, Mark Cornelsen, have been seen out together several times, most recently at Elton John’s Oscar Party. They met while they were both volunteering for the Mathew Shephard Foundation, which strives to increase awareness and acceptance for gay youth. (Matthew Shephard was a 22 year-old gay man who was brutally murdered in a hate crime in 1998. His assailants are both in jail for life.) Cornelsen is on the “youth advisory counsel” for the foundation and is listed as a “freshman as San Francisco State University… majoring in Resort and Commercial Recreation Management.”

They met when Knight was a presenter at an event for the foundation:

The actor and his new companion first crossed paths last October at a star-studded awards event the Foundation hosted in Los Angeles.

“T.R. acted as a presenter, and he was immediately drawn to Mark, who was singled out as a scholar at the event,” revealed an insider.

“Although there was some chemistry, T.R. was seeing someone else and he didn’t want to jump into a new relationship…”

After [T.R.’s last relationship] fizzled, [he] hooked up with Mark.

[From The National Enquirer, print edition, March 10, 2008]

According to Cornelsen’s bio on the Matthew Shephard Foundation website, he was disowned by his family after he came out to them. He sounds like an accomplished and caring person, as he does a lot of volunteer work and is active in extra-curricular activities. Is he mature enough to have a 34 year-old partner though?

I’m Knight’s age and I don’t know what I would have in common with a 19 year-old, not that I haven’t checked out guys who were that age and felt guilty afterwards. 14 years makes a huge difference at that age as one person already has an established career and the other is just out of high school. They do look cute together though.

T.R. was previously linked with hot Brothers and Sisters star Luke MacFarlane after they were photographed together. The Enquirer claims that he was last in a longterm relationship with “stage actor” Adam Armstrong, but that they couldn’t maintain a long distance relationship as they each lived on separate coasts. Knight and Cornelsen live in LA and San Francisco, which is a much more manageable distance.

Thanks to Just Jared for the header image taken at Elton John’s Oscar Party.