Yardley Makefield Marine Rescue leaves the Yardley boat ramp heading down the Delaware River. File/AP

The body of a young girl was recovered Friday in the Delaware River and was believed to be a 2-year-old who was one of two children swept away from their family's vehicle by a flash flood last weekend, authorities said.

The body was found in the early evening near a Philadelphia wastewater treatment plant about 30 miles (50 kilometres) from where Matilda Sheils was carried away, authorities said in a nighttime news conference.

By physical description, authorities believe the body to be Matilda’s. The Philadelphia coroner will conduct an autopsy Saturday.

The search continues for Matilda’s 9-month-old brother, Conrad.

The family from Charleston, South Carolina, was visiting relatives and friends when they got hit by a "wall of water,” according to Upper Makefield Fire Chief Tim Brewer.

Their mother, 32-year-old Katie Seley, was also killed in the flood, authorities said.

The children’s father, Jim Sheils, grabbed the couple's 4-year-old son, while Seley and a grandmother grabbed the other children, Brewer said. Sheils and their toddler son made it to safety, but Seley and the grandmother were swept away. The grandmother survived.

Four other people drowned in the area, according to the Bucks County Coroner’s office: Enzo Depiero, 78, and Linda Depiero, 74, of Newtown; Yuko Love, 64, of Newtown; and Susan Barnhart, 53, of Titusville, New Jersey.

The deaths and the search for the children have led to an outpouring of support, particularly in social media, in the suburb about 35 miles (60 kilometres) north of Philadelphia.

Associated Press