Siddhant's body was found submerged in the Eel River about 6 miles (9.6 kilometers) downstream from where the family auto reportedly crashed, Mendocino County Sheriff's Office Capt. Gregory L. Van Patten said in a statement.
Searchers have found the body of a 12-year-old boy in a Northern California river - the last of four family members who died when their auto plunged into a rain-swollen torrent. Separately, an adult female body recovered on Friday from another area of the river was identified as Soumya Thottapilly, 38.
"An autopsy is expected to be performed this week as part of the Coroner's investigation into the incident", it added.
A team on a boat smelled gasoline about half a mile (1 kilometer) downstream from where the crash was reported and found the SUV.
The vehicle was encased in sediment and visibility was poor but divers believed there was at least one body inside, officials said.
Soumya's body was found several miles from where the vehicle went into the water. Crews partially removed the vehicle with a tow truck and recovered the bodies, the sheriff's office said.
The bodies were recovered on Sunday inside the vehicle, a Honda Pilot, which was recovered from about 4-6 feet of the Eel River.
The boy's body was found about six miles north of where the family's vehicle was said to have crashed. They were driving from Portland, Oregon to San Jose in Southern California.
An inter-agency search and rescue team has recovered two more bodies of an Indian American family who were feared drowned in a California river some 10 days ago, United States officials said on Tuesday. Authorities say they believe the crash was intentional. They, however, failed to show up at the friend's place on April 6 and were officially declared as missing on April 8.
Further south, authorities were still looking for the missing members of a different family whose SUV plunged off a towering ocean bluff along the Pacific Coast Highway last month.