Two Daddies for Christmas — Felice Stevens

Two clueless men.
One determined little girl.
A whole circle of friends who've grown tired of waiting.
You are hereby invited to the wedding of the king of New York City nightlife, who's finally marrying his prince charming.

Too bad neither of them know it's happening.

this is an 11,000 word short story set in the Breakfast Club universe, but it features surprise guests from other series.