Leighton Meester and Adam Brody think their relationship is "good for a laugh"

Asked if they ever laugh about their TV alter egos getting together, Adam, 37, said: "Occasionally. Once a year, randomly, on our Seth and Blair day. It's good for a laugh."

Leighton, 31, added to 'Entertainment Tonight': "It doesn't excite us, I think, because we're just human beings... but it's exciting to us that it's exciting to you. It's cool."

However, the couple - who have 21-month-old daughter Arlo together - admitted they didn't actually watch each other's shows when they were on screen.

Away from acting, the couple have been working with Feeding America - the nation's largest hunger relief organisation - in a bid to raise awareness of the child hunger crisis in the US, and though they find the work rewarding, they admit helping serve lunches to youngster can be quite nerve wracking.

Speaking as they helped serve lunches at a Los Angeles school, Adam said: "It's weird, but I actually get a little nervous that [the kids are] not going to like me. Well, they're just like, 'I don't care, I'm eating lunch. Who's this jerk?' You know, and so the fact that they engage and seem to have a good time, that's wonderful. I wasn't prepared."

Leighton added: "It's really nice to get to see them one on one and actually have contact with them and see the difference that you're hopefully making, and to be able to play. They're so much fun. And they're so smart, and cool and awesome."

When Arlo gets older, the couple are keen to encourage her to give back and help others.

Leighton said: "She's too little to come here today. She'd be like, 'I don't get it.' But I think it's a really, you know, even for us, this is something we're sort of even learning about, and I think that it's really important to show your children that there are different sides to everything.

"It's something that people I think don't talk about. This is a crisis. This is a huge issue.... I mean, this is a summer hunger campaign for the awareness of all the kids in America that don't have food during the summer.

"So, I think you sort of take that for granted and I think to just instill in your children, or to just teach your children and also remember yourself, you're super lucky. And also it's good to reach out and to help and just to remember that."