A Northwest Arkansas 13-year-old was flown by medical helicopter to Little Rock on Friday after contracting an E. coli infection, his family said.

The boy’s grandfather posted a message on social media saying the teenager had an E. coli infection that was affecting his kidneys and liver. The boy’s spleen is also swollen, the grandfather said.

The grandfather posted an update Saturday saying the teen’s kidneys are better, but he still has low blood platelets.

A social media post by the boy’s father from Friday stated he was in Bentonville that day before being airlifted to Arkansas Children’s Hospital in Little Rock.