(WTRF) — Child protective services in Kentucky is investigating the parents of a 6-year-old boy who allowed the child and other children in their family to compete in a 26.2-mile race in Cincinnati last week, according to ABC News.

Ben and Kami Crawford posted a photo Instagram of what they say is a CPS worker interviewing one of their children, say reports.

The Crawfords allowed their children, including their 6-year-old son Rainier, to run the Flying Pig Marathon in Ohio on May 1. The parents posted the run on social media and received lots a backlash, say reports.

Ohio 6-year-old runs marathon; Parents defending action

One doctor told ABC News that children can suffer many health problems from strenuous exercise including dehydration and “electrolyte abnormalities, nausea, vomiting, heatstroke.”

Campbell County, Kentucky, District Attorney Steve Franzen confirmed that child services had visited the Crawfords, but said no determination had been made yet in the investigation, according to ABC News.