He called my baby dumb...

So my daughter (1yo) boyfriend (28yo) and I (24yo) were at the park playing. She kept trying to run into the parking lot and he goes “what is she, dumb?”

We’ve been together for a year and I’m in shock. I left the park with her and now I’m just not sure what to do. He didn’t apologize or anything, was just mean.

I plan on breaking up with him but is that me being too sensitive? Or did he cross a line?