Former Yankees outfielder Brett Gardner’s 14-year-old son died of “asphyxiation” while on vacation with his family at a Costa Rican resort, according to a report.

Miller Gardner was staying at the upscale Arenas Del Mar Beachfront & Rainforest resort when he fell seriously ill along with several members of his family, local officials told Inside Edition.

Officials are currently working with the family to transfer Miller’s body back to the US, the outlet reports.

The US State Department confirmed to The Post that Costa Rican authorities are actively investigating his death, and closely monitoring local authorities’ investigation.