The body was found as crews searched for the family along the Northern California river where it is believed they may have been swept away in heavy rains, the Mendocino County Sheriff's Office said at a Friday news conference.
On April 6, a auto was reportedly submerged in the Eel River, a little north of the town of Leggett, during heavy rains.
The bodies of Jennifer and Sarah Hart were found March 26 inside the family's SUV, which had crashed at the rocky shoreline below a cliff in Mendocino County.
Investigators began to examine the possibility that the disappearance might be linked to a report that the highway patrol received on April 6 of a vehicle plummeting into the Eel River from USA 101, a north-south highway that runs through Washington State, Oregon and California.
Around the same time, the Harts were gearing up to adopt other children.
After one of the children came by asking for food on March 23, the neighbor contacted authorities, who sent an investigator by the home late that afternoon.
The Eel River on the day the vehicle was lost.
The parents appear to have been aided by limited communication between state agencies and the absence of a central nationwide registry for child abuse or child welfare reports.
The mother said her daughter told her a boy pushed her down causing injuries. Jennifer Hart pulled the girl aside and the child agreed to leave, the report said.
She says that the government benefits calculator took into account the combined benefits she was already receiving, and then considered the amount of money that was also coming into the household via other forms of benefits.More news: Search for woman in murder investigation has extended to Florida
More news: October Box Office Day 2 Early Trends: Takes A MASSIVE Jump!
More news: Saina Nehwal Defeats PV Sindhu
She cited a trip to Lambeau Field, all three of them carrying footballs, in hopes of nabbing an autograph from running back Ahman Green.
The county coroner is working on recovering the body, which Van Patten believed at 1:10 p.m. was still in the water.
Downs, who lived in an alley off Handyside Street, behind Fenders Bar in Belize City, had just come down from her house.
The 100-foot (31-meter) drop killed the women, both 39, and their children Markis Hart, 19; Jeremiah Hart, 14; and Abigail Hart, 14.
Portland police Sgt. Bret Barnum, left, and Devonte Hart, 12, hug at a 2014 rally in Portland, Ore., where people had gathered in support of the protests in Ferguson, Mo.
Sheriff Tom Allman has described the crash as "a crime".
Authorities did not elaborate on items that were found in the river this week, but said that a vehicle seen going into the river on April 6, when a massive storm swamped areas of Northern California.
There were no skid marks at the scene, Carpenter said.
Jen Hart had a blood-alcohol level above the legal limit, said Olegario Marin, a public-information officer with the California Highway Patrol.