It is narrated from Sayyidah Umm Salamah (may Allah be pleased with her) that she said: I said: O Messenger of Allah (peace and blessings be upon him), is there reward for me regarding the sons of Abu Salamah (may Allah be pleased with him) if I spend on them? I am not going to leave them like this and like this (in need); they are my sons as well. He (peace and blessings be upon him) said: "Yes, you will have reward for whatever you spend on them." Muslim narrated it in the Sahih from Abu Kurayb, and al-Bukhari recorded it through another chain from Hisham.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب النفقات / 15736