Constipation

Baby has been constipated going on 4 days now because of the solids. I stopped giving him solids (only breastfeeding) until he has a bowel movement. What are yall giving your babies to remedy it? I remember this happened with my first child and the pediatrician recommended prune juice mixed with water....I don’t remember the ratio though or frequency. I also remember sticking that Windi tube gas majig thing up his butt, which I don’t want to do 😬.My baby typically has 1-2 bowel movements a day so 4 days is too long for him.