Ben is on enfalac for 12 months... thinking of changing to silimac2 for 6 months since he need to change sooner or later. On Enfalac everything's good... poo daily. Tried Enfapro for 6 months, he merlion after every feed. So now try similac2 for 6 months on advise by pediatrician.. But ben didn't poo for 2 days ....Any advise?