Final answer:
The action to avoid when caring for a child with a spica cast is encouraging range of motion exercises, as the cast must remain immobile for proper healing.
Step-by-step explanation:
The action that should be avoided when caring for a child with a spica cast is encouraging range of motion exercises. A spica cast is a type of orthopedic cast used to immobilize a part of the body, often after a surgical procedure or to allow a broken bone to heal properly. It is essential that the limb or area in the cast remains still; therefore, range of motion exercises could disrupt the healing process. Instead, care should focus on keeping the cast exposed to air to allow it to dry fully and prevent moisture from accumulating, which can lead to skin breakdown. Additionally, elevating the casted limb can help reduce swelling, and monitoring for signs of skin breakdown is crucial for preventing complications such as infections or pressure ulcers.