My near two year old daughter was playing with my near three year old nephew in their Nana's front room, while she (my mil), dh and I sat and had a cuppa.
Mil was talking and the play got a little boisterous, but nowhere close to me thinking I needed to intervene, but mil decided she needed to give a warning to my nephew:
'Play nice. She's only a girl'
Not 'only a baby' , or 'only little' or even 'only a little girl' but ONLY A GIRL.
I actually involuntarily facepalmed for the first time in my life and dh had to subtly restrain me. I didn't say anything, I was too stunned, then the phone rang and I just sat there with my mouth wide open while my husband whispered 'I know, I know'.