Happy 21st birthday today (Sept. 16) to Nick Jonas! The youngest Jonas Brother marked the milestone in Las Vegas with family and friends, including girlfriend Olivia Culpo and big brothers Joe and Kevin.

But what happened in Vegas did not stay there, as he shared photos of the celebrations on social media.

Big bro Joe had publicly promised to get Nick wasted on his 21st, but the party seeemed to be a classy affair, with all present dressed in their finest. Not a birthday shot is spotted, instead with participants seen elegantly sipping champagne.

Nick poses with his beauty queen.

A birthday cake that truly takes the cake.

The assembled party, dressed to impress.