The phrase "child's body" can refer to the physical form of a young human, but there are many synonyms that can be used to describe this concept. Some alternatives may include "juvenile physique," "youthful frame," "little one's figure," or "small person's anatomy." Other possibilities might include "junior build," "minor stature," "youngster's shape," or "adolescent structure." Depending on the context and tone of the piece, different synonyms may be more suitable. Regardless, each of these phrases seeks to capture the unique characteristics and qualities of a child's body, conveying their innocence, tenderness, and developmental potential.