Musannaf Ibn Abi Shayba 19:657

Abu Bakr narrated to us, he said: Ma'n ibn 'Isa narrated to us, from Ibn Abi Dhi'b, from al-Zuhri, who said: There is no prescribed punishment (hadd) for a young boy who is slandered while he is young, until he reaches the age where prescribed punishments become obligatory upon him.