Musnad Abu Ya'la al-Mawsili 18:3

Muhammad ibn Bashar narrated to us, Ghundar narrated to us, Shu'bah narrated to us, from Abu Bishr, from Salam ibn 'Amr, from a man among the companions of the Prophet, may Allah bless him and grant him peace, from the Prophet, may Allah bless him and grant him peace, who said: "Your brothers, treat them well," or he said, "do good to them. Seek their help with what overcomes you, and help them with what overcomes them."