Husbands parents

My inlaws are the sweetest people but they are on my last nerve. I have a son from a previous relationship, his father is not involved so my husband is his dad. We went camping with my father in law and his gf of 5 years who my son sees as his grandparents. My son was tired and had a fit which I took care of and had him in time out. Obviously he started crying and his grandpa did want to hear it and went over and threatened him with 'do you want something to cry about?' And then took him out of timeout. My husband was in the camper sleeping. My father in law even said grand parents overrule moms and dads. I have told my husband I don't like anyone overruling my parenting. I really don't know what to do. If they are watching him that is one thing but if I/my husband are there it is our job. He won't stand up to his dad and I feel like it is his parents his responsibility.