The Play Lab is led by Lisabeth DiLalla, PhD, a developmental psychologist at the SIU School of Medicine, and is home of the Southern Illinois Twins, Triplets and Siblings Study (SITSS). The lab focuses on preschoolers and the development of peer interactions and parent-child interactions from early childhood through adolescence.There are several research projects underway at the Lab. The SITSS primarily focuses on preschoolers, with various projects encompassing the development of peer interactions and parent-child interactions from preschool through adolescence.