Idiopathic Early-Onset Scoliosis is a spine curve that appears in young children. This study compares two treatments: casting and bracing. Casting involves using plaster or fiberglass to keep the spine in place, while bracing uses a removable support worn all day. The study aims to find out which method works best by following children until their spine curve either improves, doesn't change after two years, or gets worse.

Children with this condition and one of their parents can join the study. The child must be under 3 years old, able to stand alone, and have a specific spine curve angle called the Cobb angle, between 20 and 70 degrees. Parents must agree and be able to fill out surveys.

• The study takes place in multiple locations and uses both random assignment and parent choice for treatments.
• The study continues until the child's spine curve changes or for up to two years, whichever comes first.
• Families will receive information to help make informed treatment decisions.