We were at urgent care today, checking Mira's foot out. She commented on a larger woman, saying (very loudly) "That's a big lady". I tried ignoring it, which prompted her to repeat herself. Eventually, I ended up admitting that she was correct, and telling her that people come tall, short, big, small, but what they look like doesn't matter.
What concerns me is that she only commented on this lady, and another, that she thought looks like my cousin (she does, a little). I've never pointed out anything along those lines, so it was kind of mortifying to hear her announce it so loudly. When the lady came and sat next to us, Mira moved, saying she didn't want her sitting there (the seats next to us had been empty until then). How would you handle this?