Is this an example of a bad parenting decision?

The little girl that I nanny for is 3 years old, turning 4 in December. She came up to me today and said "Mommy gave me a tattoo, just like the girls in the movies!" Then she turned around, bent over, and lifted up her shirt to show me her temporary tattoo just above her . Like a TRAMP STAMP! I could literally see her and it looked really trashy. I understand that it's a temporary tattoo but doesn't it seem kinda off that a mother would put that on her child? Wouldn't most mothers but a erfly on the girls arm or a horsie on her tummy or something? Why a tramp stamp? Is it inappropriate or do you disagree?