Constipated toddler

Nicole • Mother of 1 beautiful baby girl 1/08/18💜🌙✨

My 21 month old has been constipated frequently and the doctors just say the same thing “apple juice/fiber”. Ive been doing both and I give her lots of water and I give her prune juice. I use to have the same stomach problems as a child and its never been fixed. Does anyone have any other tips I can try? :((