It is narrated from Sayyidah Umm Salamah (may Allah be pleased with her) that the Prophet (peace and blessings be upon him) said: "Whoever spends on two daughters, or two sisters, or two female relatives, hoping for reward from Allah for that spending, until Allah makes them independent (of him) and enriches them from His bounty, they will both be a screen for him from the Fire."
Hadith Referenceالمعجم الكبير للطبراني / مسند النساء / 20240