Musnad Abu Ya'la al-Mawsili 2:60

Narrated to us Zuhayr, narrated to us Sufyan ibn 'Uyaynah, from 'Ubayd Allah ibn Abi Yazid, from his father: He heard Umar ibn al-Khattab saying: The Messenger of Allah (peace be upon him) said: "The child is for the bed."