I was actually talking to my mother about her vaccine scar today. She says she had a friend who got vaccinated the same time she did. But her friends mother was super vain, so told the vaccinator guy to give her daughter the shot on her thigh, so a swim suit would cover it.

But outer thigh is lower than where bathing suits show so you saw the scar anyway, and the mother was pissed. Mother's friend didn't care though, since she was a kid.