Britney Spears wore Level 99 cut-off shorts to hit the sand with her sons Sean Preston and Jayden James in Santa Barbara, CA, on Saturday. The trio was joined by a group of assistants and took advantage of the warm Southern California weather during their beach day. It's an exciting weekend for Britney and her family, since her younger sister, Jamie Lynn Spears, got engaged to boyfriend Jamie Watson. Jamie Lynn took to Instagram to share the big news and showed off a snap of her round diamond ring for her fans. Britney congratulated her on Twitter, writing, "So excited and happy for my sister, congrats Jamie — love you."