Baby always constipated

My dd is almost 11 months old she is ebf and we started solids around 6 months. Since maybe almost 7 months old she is always constipated. I cut out the cereal hoping it would help but it hasn't. Doctor thought it was from the summer heat so we would make sure she'd drink 4 oz of water with tiny bit of juice a day and it helped but. Ow she doesn't really want the juice as much. She eats fruits for breakfast but doesn't eat a ton and veggies at night. Some snacks during the day. She loves people food now like cheese, noodles or anything we eat that she. Can gum. But I feel like she's always backed up. We'll go through 4-5 days of her not going then she'll push for a day and push so hard she throws up. It's only hard little bits at first then she'll go a lot and be good for a few days then it happens again. I feel so bad for her idk what else to do. We've tried doing prune juice everyday but I think it upsets her stomach sometimes. Any advice or similar situations?