Children make erratic movements that trigger the rooster to defend his flock. With your daughter being that young, I would either keep him locked up or rehome him. While your rooster did nothing wrong, he was just doing what is ingrained in him, you have no way of keeping your daughter from being a child. She's going to run, play, jump, etc and you just don't know when it could happen again. And it happens so fast. I'm 5'8" and I've been hit as high as waist level - he could very easily get her face.
If you are going to keep him and keep him locked up, I'd definitely take out his spurs or at least round them so they aren't pointy. I've taken those dremel like dog toenail trimmers to the rooster that nailed me.