Amber presents with her 3 year old daughter Reena, as she is concerned that for the past 5 days, her child has not opened her bowels. Usually Reena opens her bowels on alternate days and has not suffered with constipation before. She states that she is normally fit and well and there were no problems at birth. Recently the stool normally looks hard and is sometimes pebble like. There has never been any bleeding. Amber admits their diet is poor consisting of frozen fast foods and thet Reena prefers to drink fizzy drinks rather than water.
On examination, her vital observations are normal and you can feel a mass in the left lower quadrant. You also note soiling of the underpants. Her BMI is on the 50th centile. What is the best treatment?