Musnad Ahmad 1482
Musnad Abu Ishaq Sa'd bin Abi Waqqas
It was narrated from Sa’d that: The Prophet (ﷺ) entered upon him to visit him when he was sick in Makkah I (Sa"d) said: Messenger of Allah, should I bequeath all of my wealth (in charity)? He said: “No” I said. One half? He said: “No." I said: One third? He said: "One third, and one third is a lot. If you leave your heir independent of means, that is better than leaving him poor and having to ask people [for help]. Whatever you spend on your family of maintenance you will be rewarded for, even the morsel that you lift to your wife"s mouth.” On that day he only had one daughter. And Sa"d mentioned migration (Hijrah) and he [the Prophet (ﷺ) said: "May Allah have mercy on the son of ‘Afra", Perhaps Allah will extend your life so that He may benefit some people through you and harm others through you.”