Nope, you didn't overstep, and good for you for calling him on it. My ex and I worked opposite schedules so one of us was with the baby and him not in daycare, and MIL filled in where necessary. SO many times she'd see that he did something like this, but wouldn't say or do anything. I'd come home from work to both of them sitting there, while the baby's diaper was about to fall off. One time, she had taken ds out all day and night without a coat in 22-degree weather. Why? Because that's how his dad had dressed him, and she didn't want to "step on his toes." You bleeping idiot!!! The fight between me and her, and then me and him, was what finally ended our relationship. SOMEONE had to stand up for this child!