Have you ever thought there was a genetic component to this? Have you ever visited boards that deal with this?
My son is 16 and he sits on the toilet as a routine after diner. Why? Because when you eat your body is naturally moving. But this was after a long time of being on Milk of Mag. (before Mirilax). Yes, I was hesitant to do this because of the side effects. However, with working with the doctor we could watch for the risk.
Heck, using flax seed oil or castor (flax seed would be nutritionally better) getting your dd pop to a consistency of baby food and then SLOWLY (we are talking months) weaning of. ML by ML of oil. Stops and Stalls.
There is hirschsprung disease. If she or your nephew has a "mild" presentation is is far more manageable and easier on them to manage it with stool softeners, diet, and routine bm patterns than surgery. However, this will not help if you do not first to "shrink" the colon. This takes a long time. It also means cooperating with you GI.
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