How old were Zayd ibn Harithah and Umm Ayman when they got married?

Knowing the biographies of the Companions illuminates the heart and endears them to us, for they are imams to be emulated. Zayd ibn Harithah, may Allah be pleased with him, is the martyred prophetic commander, the beloved of the Messenger of Allah, peace and blessings be upon him, mentioned in Surat Al-Ahzab. Zayd lived in the house of prophethood and was called "Zayd ibn Muhammad" until the verse (Call them by their fathers' names) was revealed. He was the first of the freed slaves (mawali) to embrace Islam, and the verse (And [remember, O Muhammad], when you said to the one on whom Allah bestowed favor and you bestowed favor) was revealed concerning him. The Prophet, peace and blessings be upon him, freed him and married him to his freed slave woman Umm Ayman, who was his nursemaid, and she bore him Usamah ibn Zayd. Zayd was about thirty years old when he married Umm Ayman, and he was martyred at Mu'tah when he was fifty-five years old. Umm Ayman passed away five months after the Prophet, peace and blessings be upon him, and it is likely that she was older than him.