My toddler is very Constipated

Ceanna

My one year is so constipated it breaks my heart. His bowels are so big it’s hard for Him to pass. I have been give him fruit, veggies, water, now I’m thinking of changing his milk. I took him to the doctors and they told me to give him Miralaz but it’s not helping. Is lactaid milk good for toddlers and which one...