Musnad Ahmad 175:13

'Abd al-Razzaq narrated to us, he said: Ma'mar narrated to us, from al-Zuhri, from 'Abd al-Rahman ibn Ka'b ibn Malik, he said: Umm Mubashir said to Ka'b ibn Malik, while he was ill: "Convey my greeting to my son," meaning Mubashir. He said: "May Allah forgive you, O Umm Mubashir. Have you not heard what the Messenger of Allah (peace and blessings of Allah be upon him) said: 'The soul of the believer is but a bird that feeds upon the trees of Paradise until Allah, the Mighty and Majestic, returns it to its body on the Day of Resurrection'?" She said: "You have spoken the truth; I seek forgiveness from Allah."