A sheriff says a French couple who perished during an afternoon hike across the searing New Mexico desert likely saved their 9-year-old son by giving him two sips for each one they took from their water bottles before the supply was exhausted.

Otero County Sheriff Benny House said Friday that the boy was in remarkably good shape when he was found alongside his dead father on a trail in the White Sands National Monument. They were located about an hour after park rangers found the mother dead Tuesday.

House identified the couple as 42-year-old David Steiner and his 51-year-old wife, Ornella Steiner. They were tourists from the small town of Bourgogne (BEHR'-goyn-ya) near the city of Reims, France.

The couple apparently died from heat-related causes.