Suggest Treatment For Child Suffering From Constipation

My daughter is 2 1/2 yrs old. She has been suffering from constipation since long and we have consulted various doctors. Everyone has prescribed some laxative or the other. She is toilet trained and her diet has been modified to some extent. She has been on Laxopeg (polyethylene glycol) powder daily for the last 1 year. We want her to get rid of this problem. Please prescribe the rt diet and any suitable medication if required