Let us say that your daughter is a lot like princess Charlotte towards both older and younger brothers, she is the boss she tells the boys how to play, what to play and what to do in general, one day your older son left the house bland writes a letter saying
" Dear mom I can't anymore, you do and say nothing as you watch how my life gets dictated by my younger sister, I left because you laugh and find it cute when she does these things Tobi's, don't bother looking for me. And keep your daughter away from me "
this is how she treats your son's the one son ran away from home because of her attitude.