Pro-social behaviors influence the development of friendships beginning in early childhood (Odom, Schertz, Munson, & Brown, 2004); potentially impacting long-term success in academic and social settings (Ladd, 2008; Lane, Stanton-Chapman, Jamison, & Phillips, 2007). High-quality preschool programs focus on increasing pro-social behaviors in young children with and without disabilities (Division of Early Childhood [DEC] and National Association for the Education of Young Children [NAEYC], 2009; NAEYC and National Association for Early Childhood Specialists in State Departments and Education [NAECS/SDE], 2002; Wolery, 2005), providing numerous opportunities for interactions (Grisham-Brown, Hemmeter, & PrettiFrontczak, 2005). However, young children with disabilities are more likely to display social delays that impede appropriate peer interactions, potentially leading to rejection from peer groups (Guralnick, 1999; Ladd, 2008; Odom et al., 2004). Young children with disabilities may require structured opportunities for peer-to-peer interactions to recognize the potentially "complex discriminative stimuli" that set the occasion for age-appropriate social behaviors (Ledford & Wolery, 2013, p. 440; Wolery, 2005)