Musnad Ahmad 1153:23

Ishaq narrated to us, Sufyan narrated to us, from Mansur and Yahya, from Sufyan, who said: Mansur narrated to me, from Ibrahim, from Umarah ibn Umayr, from his paternal aunt, from Aisha, from the Prophet, may Allah bless him and grant him peace, that he said: "Indeed, the best of what a man eats is from his own earnings, and indeed his child is from his earnings."