Musnad Ahmad 1007:8

'Abd al-Rahman ibn Mahdi narrated to us, Malik narrated to us, from 'Amir ibn 'Abd Allah, from 'Amr ibn Sulaym, from Abu Qatadah, that the Messenger of Allah (peace and blessings of Allah be upon him) used to pray while carrying Umamah bint Zaynab. When he bowed and prostrated, he would put her down, and when he stood up, he would carry her.