Probably, in subtle ways. This goes completely against what I think about the matter, and I try to be aware of it and compensate for it, but it seems to come from subconscious biases that have nothing to do with reason.
I feel differently toward girls than toward boys. That goes way back. I feel more tenderly toward them; I’m more inclined to like them; I feel more at ease around them. Realistically, all of that feeling differently must translate into a different way of interacting with them.
I have a son and a daughter, both adults now. I think it’s perfectly normal for parents to have different relationships with each of their children regardless of gender, so it’s hard to know how much of that difference is due to gender, birth order, personality, etc. I do treat them differently, not in blatant ways related to how I think boys and girls ought to be treated, and certainly not in preferring one to the other, but in ways that I only catch when I’m paying close attention.