The study results are expected to be important to inform the field of infant rehabilitation and provide much-needed evidence about whether infants and toddlers show significant (clinically meaningful) benefits from one or more of the 3 forms of therapy being tested. The findings will include evidence about both behavioral and brain changes. Further, the evidence will answer questions about whether the immediate therapy benefits, if detected, continue to be measurable at 6 and 12 months after therapy has ended. In addition, the study will yield first-ever evidence about whether CIMT is stressful for children and their parents. It may be there are some children or parents who are at higher risk for showing stress effects. If so, the data generated by this study will be important for future clinical practice and research to reduce these levels. If elevated stress does not occur, or if markedly lowering of stress is detected, then these findings will help to resolve the uncertainty that currently prevents some families or clinicians from considering this form of therapy, despite the fact that other scientific studies have shown it produces large and lasting benefits for children age 2 and older.