Regardless of theoretical orientation, there is no doubt that children should enjoy playing (Lifter, Foster-Sanda, et al.,
2011). However, because happiness and enjoyment are difficult constructs to directly measure, behavioral researchers rarely
address that aspect of play. This study extended previous research by demonstrating that two out of three participants’
(Ashley and Vince) mothers believed their children were happier, in a better mood, and more interested in play following
intervention. When asked why they provided these ratings, the mothers pointed out that they observed their children
smiling and giggling more during play post intervention. Further, both Vince and Colt’s mothers indicated that the reduction
in stereotypy suggested that their children were ‘‘calmer’’ and ‘‘less frantic’’. Colt’s mother’s ratings did not change from preto
post-intervention. In response to questions about those ratings, Colt’s mother stated thatthe reduction in stereotypy was a
notable improvement but that she still felt that his play skills needed further improvement. These data should be considered
with appropriate caution given that the ratings scales utilized (i.e., MSRIQ and GCARS) lack psychometric evaluation and
because any such rating scale can only provide indirect evidence, particularly when used to describe the feelings of another
person. Despite these concerns, we believe that mothers may be the best available judges of the feelings of their children or,
at least, that the mothers’ perception of their child’s happiness is a socially valid outcome measure. Regardless, future
research could seek to identify alternative methods for more directly measuring changes in child happiness following the
acquisition of play skills.