Paige has knack. She can pile just about anything into a tower, a line, or a path. She gathers colors, sizes, shapes, and objects and puts them in their places. Toddlers like Paige normally sort as a way of learning similarities and differences, but when this behavior interferes with other activities, Obsessive Compulsive Disorder might be the reason. Little ones with OCD get overly upset when their routine changes. Repetitive behaviors like washing, counting, or lining up of objects when used to control their world may be a clue. Children with OCD don't understand why they like order. They only know it feels right for their things to be 'just so'.