Chris Brown -- Two Huge Falls at Las Vegas Birthday Bash (VIDEO)

Chris Brown's birthday celebration on the Vegas strip had bottles poppin', hot chicks dancing, and ... absolutely adorable little baby videos.

Yeah, Chris' 26th bday party at Drai's was way different from his others, because this one featured home vids of Royalty on a big screen -- and you've gotta see the look on Chris' face ... daddy's totally fallen for his baby girl.

The video is pretty wild for a few reasons -- Chris hands out Ace of Spades bottles to fans in the crowd ... Chris shows off his badass dance moves ... AND Chris spins and goes flying off the stage!

Breezy also got the champ to come out -- Floyd Mayweather Jr. showed up flashing a tiny bit of the more than $200 mil he earned at the office last weekend.