The bodies of Elasar Manzanares, 37, and his 11-year-old daughter, Lupita, were recovered after the tragedy Sunday at Lake Somerville, a popular recreation site. A search was continuing for his 8-year-old son, Jorge, and 9-year-old nephew, Kevin Manzanares.
Jose Rangel, 22, who tried to help rescue them, died later at St. Joseph Regional Health Center in Bryan.
The swimming hole has been the site of numerous drownings in recent years, Burleson County Sheriff Gene Barber said.
"There's somewhat of a drop-off," he said, "and it startles people when they step off and can't feel the bottom. This is the place people love to come to wade, but it's dangerous when they get out too far."
The family came to Welch Park at about 4 p.m. and the children began wading in the lake but later began having difficulty staying above water, Barber said. Manzanares, Rangel and a third man attempted to rescue them. The third man started having trouble swimming and returned to shore.
"He said that when he turned back around, the others were already under water," Barber said.
Lake Somerville is about 25 miles southwest of College Station in east-central Texas.