John Muldowney, the son of drag racing icon Shirley Muldowney, died of a blood clot Thursday at the age of 59 in Springfield, Mo.

John Muldowney was the only child of Shirley Muldowney and her first husband Jack. He worked on Shirley Muldowney’s dragsters throughout her driving career and has since worked for a variety of other teams, machine shops and fabricators.

In lieu of flowers, Shirley Muldowney is asking friends and fans to consider making a donation to Shirley’s Kids, the 501(c)(3) charity created in her honor that helps kids in need at various stops on the NHRA tour. Donations can easily be made at ShirleysKids.org.