We spotted Jennifer Lopez vacationing in Miami, Florida, at the SLS Hotel pool yesterday with her boyfriend Casper Smart and her twins Emme and Maximilian.

The four of them swam around the pool, and at one point Casper lifted Emme over his head before splashing her down into the water. Casper also had fun with a water gun.

Lopez was surrounded by security, and one bodyguard held an umbrella over the singer/actress while someone shot video of her. Lopez is planning a new documentary about her life called "Dance Again." The film will be released in 3D.

Lopez and Enrique Iglesias are finishing up their joint North American tour, and the pop star will continue solo in Europe, Asia and Australia.

The singer is certainly keeping busy these days. She's also starring in the upcoming film "Parker" opposite Jason Statham about a thief who lives by a code of honor that includes never stealing money from people who need it.

See more photos of Jennifer, Capser and her kids soaking up the sun...