3 boys 1 girl

Calling all moms with children, who have both boys and girls, and specifically all of one and only one of the other. I need some advice! I have three boys and one daughter…no problem right????? Wrong!!!!   Lady bug does NOT like to share her stuff. She will turn 6 in a few months and is completely capable of sharing her things BUT they are all girly things…dolls, pinks and purple things. You get the picture. Her brothers love to play with her but she just won’t let them any longer. Should I let this continue because this is “girly” stuff OR should I make her share everything?…Just curious what your thoughts are and how you handle such things!