Hazrat Aishah (may Allah be pleased with her) said that a man said: O Messenger of Allah! Should a slave be freed on behalf of my father? He (peace and blessings be upon him) said: "Yes."
This is how it was reported to us, and it is an error.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الوصايا / 12640