Jennifer Lopez celebrated her 43rd birthday on Tuesday (July 24), though you wouldn’t know it by the timeless diva’s youthful looks. That cozy lunch with boyfriend Casper Smart wasn’t the only b-day celebration J. Lo had planned for the day. The “Goin’ In” singer donned her tightest, most back-baring red dress for a night out at sea, where family and friends joined her for a massive yacht party. The ex-American Idol judge appeared to have a good time after dancing and laughing all night long, though we probably would, too, if our boyfriend tweeted something as sweet as: “(yelling) HAPPY BIRTHDAY TO THE MOST BEAUTIFUL BEAR IN THE WORLD!!!!!!!!!!!!!!! LOVE U.. ;) @JLo“.