Katie Holmes and daughter Suri
07/19/2011 AT 06:00 AM EDT
A bikini-clad Katie Holmes
enjoyed a family pool day in Miami Beach with hubby Tom Cruise
and daughter Suri
. The trio hung out at the SoHo Beach House
where, a source says, "they were keeping cool in the water while the temperature was in the mid-90s." Adds the source: "[They] seemed to be having a fun family play day."