The body of a girl found in a river in Philadelphia on Friday is strongly believed to be that of 2-year-old Matilda Sheils, who was swept away along with her brother by floodwaters a week ago, authorities said.

The boy’s body was found in the Delaware River near the city’s sewage treatment plant after 911 callers reported the body shortly after 5 p.m., Upper Makefield Fire Chief Tim Brewer said.

Matilda Sheils and her 9-month-old brother, Conrad, have been missing since Saturday when flooding hit Bucks County, killing their mother.

“Based on the physical description of the child and the clothing found on the child, we strongly believe that 2-year-old Mattie Sheils has been found,” Brewer said at a news conference.

Philadelphia police said their marine unit recovered the girl’s body and she was pronounced dead at 5:30 p.m.

Two people who called 911 reported a body in the river. The first was at 5:04 p.m. but had limited information, Brewer said, and the second at 5:06 p.m. had more details, including a location.

The boy was found in the rubble against a pier, Brewer said. He called it a tragedy and said the entire community has been affected and his thoughts were with the children’s family.

“We can’t begin to comprehend the pain they’re experiencing,” Brewer said.

The body was found 32 miles from where the children were lost, Brewer said.

The search continues for Conrad. Philadelphia police aviation and marine units searched the river for him Friday, he said.

«We’ll be in the water tomorrow, as scheduled,» Brewer said. «We will work tirelessly to ensure that Conrad is found.»

There were six people in total in a vehicle that was stranded in floodwaters, authorities said.

The children’s father grabbed a 4-year-old boy and pulled himself to safety, and Matilda and Conrad’s mother and grandmother grabbed those two children, but all four were dragged away. The grandmother survived.

The flooding occurred at Washington Crossing where 11 vehicles were inundated. Up to 7 inches of rain hit the area, which sits along the Delaware River, in less than an hour, Brewer said.

In addition to the children’s mother, Katheryn Seley, 32, four other people died in the flooding, authorities said.

They were identified by the Bucks County coroner as Enzo Depiero, 78; Linda Depiero, 74; Yuko Love, 64; and Susan Barnhart, 53.

denis romero contributed.