(CNN) – The castaway who washed up in the Pacific after being lost at sea is back in the hospital.
Jose Salvador Alvarenga, who said he was adrift for 13 months, needs IV fluids, according to a Mexican official.
The fisherman's shipmate did not survive and his loved ones are now searching for answers.
More than a year after her son went missing, a mother is now grieving his death.
"For me it was a devastating blow," Roselia Rios said. "The pain is so great I can't explain it. It wouldn't wish this on anybody. Losing a child is the hardest thing to bear in life."
Ezekhial Cordova, a 23-year-old fisherman, is believed to have died at sea during a failed fishing trip he was on with Alvarenga.
Cordova's family lives in El Fortin, a rural village. His bedroom is as he left it.
"My brother was kind, he was responsible with my mother," Jovani Cordova said. "In fact he worked in the sea because of her. He wanted to improve himself. He didn't want to be poor like us."
The local road is so bad, it's easier to travel by boat, and a short ride took Cordova to where he worked.
Fishermen say the boat left from Costa Azul, sailing out to the open Pacific Ocean. The boat the men fished in was open and exposed to the elements.
Bellarmino Rodrigues was the owner of the boat that went missing.
"My colleagues went to fish and the next day they told me by radio that the engine failed and the GPS device was wet," Rodrigues said. "We went to search for them for 7 or 8 days with the authorities. The governor gave us a small aircraft but it was impossible to find them."
Alvarenga, who says he survived more than a year at sea, and Cordova, both belonged to a cooperative of 45 boats called Cameroneras de la Costa.
The cooperative fishermen make an average of $150 a week.
"Fishing here is very dangerous because there are strong winds," fishing cooperative official Salatiel Medina said. "This began with a cold front and with that came strong winds of 120 kilometers an hour."
Back at the family home, Roselia Rios is now focusing on one thing.
"As I mother, I demand that the authorities allow me to talk to the survivor," Rios said. "Only in that way will I know what happened and what he did with the body of my son. I deserve the truth."
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