Serial model and actress dater Joe Jonas celebrated his 24th b-day last week (Aug. 15) and he admitted that his birthdays have less impact now that he's getting older. With Father Time catching up to the hunk who dates hotties like it's his job, Joe Jo is more interested in helping his little brother Nick Jonas wet his whistle for his 21st birthday this year.

That's Sept. 16, all you calendar watchers.

"It’s starting to get where it’s not as exciting anymore you know?," the middle Jo Bro said about his big day. "And it’s just kind of another year."

But as for his baby bro? "It’s an interesting year. Nick is turning 21, so I’ve been focusing on his party planning and making sure that he is fully intoxicated," Joe said. Now that's what we call looking out! Even though Nick is diabetic, so that's probably a little more dangerous for him than for most.

While birthday No. 24 may be ho-hum for Joe, he did recall the debauchery of his 21st, saying, "I ended up on the bottom of a flight of stairs. I don’t know how that happened. I spent it in a college town and we went with a bunch of our friends and there was a thing going around called ‘icing’ where you get Smirnoff Ice and someone has to secretly hand it to you and you get on one knee and you have to chug it ... I can’t go near a Smirnoff Ice anymore."

Hey, at least he has some good memories, right?

Listen to Joe Jonas Talk Birthdays + More With Ryan Seacrest