The children who died have been identified as 4-year-old Dennis Clayton Lennon and 14-year-old Ciara Puskas. Both were from Umatilla, which is between Lake George and Orlando.
They were among five children and two adults on a 20-foot boat that capsized during a strong thunderstorm on Lake George Sunday evening.
The Florida Fish and Wildlife Conservation Commission (FWC) says Dennis Todd Lennon, the operator of the boat, started to reel in the anchor as everyone else remained below in the cabin.
Two waves came over the bow of the boat, sending water into the cabin. Another wave hit which caused the boat to capsize, trapping six people in the cabin.