Purity: Cross-Gender Ghusl for Children

Practical Laws of Islam as per the teachings of Ayatullah Sistani

Ruling 548:

A man can give ghusl to a young girl who cannot discern between right and wrong. A woman can give ghusl to a young boy who cannot discern between right and wrong.

-Ayatullah Sistani, Practical Laws of Islam, Purification (Taharah)