Musnad Abu Ya'la al-Mawsili 159:79

And with his chain of narration, that the Messenger of Allah (ﷺ) said: "O sons of Abd Manaf, purchase yourselves from Allah. O sons of Abd al-Muttalib, purchase yourselves from Allah. O Umm al-Zubayr, aunt of Muhammad, O Fatimah, daughter of Muhammad, I do not possess anything for you from Allah. Purchase yourselves from Allah. Ask me of my wealth whatever you both wish."