Jennifer Lopez and Alex Rodriguez do EVERYTHING together now ... including celebrating their birthdays, and she even got him on the dance floor for the event.
The couple hung out with friends and family Saturday night in Miami for a massive birthday party -- hers is July 24 and his is July 27 -- and while J Lo always has on her dancing shoes ... we don't normally see A-Rod cut loose. Dating Jennifer clearly changes a man.
Things to look for in this video: - A-Rod & J Lo's "Sweet Caroline" singalong - Towering double birthday cake - Jennifer's killer see-through outfit
And don't let 'em fool you ... Jenny's still from the block, which she proved with some ass-shaking moves when the DJ put on her song, "Ain't It Funny."