help with weaning my 11 month

So I have been breastfeeding for literally 3 years. I had my first son feb 2015 breastfeed him then I had my second son may 2016 and he's still breastfeeding. I want to wean him but I am not sure how to do it. I don't want to introduce formula because he is almost a year. My older son is allergic to dairy so he will have almond, coconut or soy milk. Can I possibly start my youngest on those? He eats a lot of meals basically everything we eat he eats. I just find at night is the worst for his feeding he comfort eats how Cani get him to sleep longer?