While Brooke Mueller is away in rehab, Charlie Sheen tweeted a photo of himself spending quality time with their 4-year-old twins, Bob and Max. Credit: courtesy of Charlie Sheen

Dad on duty! Charlie Sheen shared an adorable new photo of himself posing with his 4-year-old twin boys, Bob and Max, on Tuesday, July 2.

In the Twitter snapshot, Sheen squats down and smiles for the camera while hugging his boys, who are playing with shark toys. "'If ya see a shark Hooper, Swallow!'" the Anger Management actor, 47, captioned the photo, stealing quotes from 1975's Jaws. "Hey M J S and B; eat this remora lose-bagz. How ya like me now? Hash tag win C."

Sheen's sons are currently staying with his second ex-wife Denise Richards while their mom, Sheen's third ex-wife Brooke Mueller, is away in rehab to get help for prescription drug abuse. (Mueller has been at the facility -- her 19th rehab stint -- since May 3.)

During an appearance on Chelsea Lately on July 1, Richards, 42, was applauded by host Chelsea Handler for helping Sheen take care of the twins. "I know you're raising his children right now," Handler said. "I know you're probably not allowed to talk about it, right?" 

"Pretty much," Richards agreed.

"Well, it's really nice of you to be doing that, though," Handler added to the applause of the audience. "You're like one of the best ex-wives ever . . . You used to get a really bad rap and you're turning out to be the coolest ex-wife anyone can hope for."