It is narrated from Sayyiduna Sa'd (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "Whatever you spend on your family, you will be rewarded for it, even the morsel that you put in your wife's mouth, you will be rewarded for that as well."
Hadith Referenceمسند احمد / مسند باقي العشرة المبشرين بالجنة / 1480