A relative of the Mexican fisherman who died during a reported 13-month sea odyssey says family members don't blame the survivor who turned up in the Marshall Islands.

The family says Ezequiel Cordoba was 22 when he set out with Jose Salvador Alvarenga in a small open boat in late 2012. Various versions of Cordoba's name and age have been reported.

Alvarenga has said Ezequiel died early in the voyage, while he survived by eating fish, turtles and birds.

Cordoba's aunt Magdalena Cordoba said Thursday the family doesn't blame Alvarenga. She said Mexico's government has promised to investigate how Cordoba died.

But it will be hard, given that Alvarenga says he tossed Cordoba's body overboard long before he drifted to the Marshall Islands, 6,500 miles (10,500 kilometers) across the Pacific.