My LO always struggled with eating foods she’s so picky and was always constipated What works for me is I use to sneak things combined in her food that I no she likes If she ate a banana I would add some oatmeal mixed in Soups I would add lentils Without her realizing and she would eat it no problem
Hope this helps
I brought the powder fiber and sprinkled it on my son food and said it was cheese. He ate it right up. I also did it with juice
Prunes also helps
Apple juice and apple sauce is honestly like baby laxatives. Always helps my daughter.
My daughter always struggled with constiparon too bcz how picky she was my dr said white grape juice helped with helping her use the bathroom and it really did I did every other day