“My mom and I were going through some hair styles yesterday, and I picked the one that I really enjoy,” said the 18-year-old, who, along with her sisters, has autism.

PRT therapists use various strategies to motivate autistic children to talk during play. For instance, they may name a toy that a child shows interest in, but hand it over only if the child then requests it by name. They also teach parents to use similar strategies in their daily routines.

Down syndrome occurs across the human spectrum and is the most common chromosomal condition. Each year, about 6,000 babies are born with Down syndrome — a 1 in 700 chance.