Sayyiduna Awf bin Malik (may Allah be pleased with him) reports this saying of the Prophet (peace and blessings be upon him): "Any Muslim who has three daughters and spends on them until they reach maturity or die, they will become a barrier for him from Hell." A woman said: "What if there are two?" The Prophet (peace and blessings be upon him) said: "Even if there are two (the same reward will be gained)."
Imam Tabarani recorded it; its chain contains a narrator, al-Nahhas bin Qahm, and he is da'if (weak).