Musnad Ahmad 941:14

Ya'qub narrated to us, my father narrated to us, from Muhammad ibn Ishaq, Sa'id ibn 'Ubayd ibn al-Sabbaq narrated to me, from Muhammad ibn Usamah ibn Zayd, from his father Usamah ibn Zayd, who said: When the Messenger of Allah (peace and blessings of Allah be upon him) became heavy [with illness], I descended, and the people descended with me to Medina. I entered upon the Messenger of Allah (peace and blessings of Allah be upon him), and he had become silent and was not speaking. He began to raise his hands toward the sky, then he lowered them upon me. I knew that he was supplicating for me.