All 3 of my kids have constipation problems since birth. is this normal?

Maybe: First and foremost, this could signal a bigger problem such as hirschsprungs disease or something else and those need to be explored. Gi consult may be needed. But - to treat constipation, fiber is key. Diet must contain fiber, and at this age you need 25+ grams per day. As reference, an apple has 3 gms, wheat bread has 1g per slice, broccoli 3-5 gms, etc. Miralax (polyethylene glycol) daily helps as well but fiber...

Possibly: Some surgical causes of constipation are genetic and acn be passed on to one's children. A GI consult and barium enema are indicated as a start.

Frequent: Constipation is a frequent complaint in children. However, three children with constipation from birth raises the concern of congenital abnormalities with a genetic predisposition, such as Hirschsprung's disease, in which the nerve cells that allow the anal sphincter to relax are missing.