I've posted before about how breastfeeding, and in particular a natural weaning process (years, not months), is a strong building block for a healthy vegan child.
Basically, if you continue to breastfeed your child along with the solids they eat, you are providing perfectly-designed nutrition. There's no need to add other milks, particularly milks from other animals, with their associated health risks and institutional cruelty.
But very few families choose natural weaning. Unlike traditional cultures worldwide, our culture has primarily sexualised breasts, mainly for commercial use. So to most, breastfeeding past infancy is icky, weird, and probably perverted. Of course, a child with a bottle of cows' milk would pass unnoticed.
The recent uproar about the breastfeeding Time cover mother is living proof of how squirmy people get when seeing a big kid attached to his mother's human nipple.
Well, I've been there, done that, and had my motivations examined with a very dirty microscope. It's time we talked about these judgements openly. I hope you'll read my frank discussion on breastfeeding mothers and sex and find it valuable in the big picture of cultural bias vs raising the next vegan generation.