Sunan an-Nasa'i 3626

It was narrated from 'Amir bin Sa'd that his father said:"I became ill with a sickness from which I later recovered. The Messenger of Allah came to visit me, and I said: 'O Messenger of Allah, I have a great deal of wealth and I have no heir except my daughter. Shall I give two-thirds of my wealth in charity?' He said: 'No.' I said: 'Half?' He said: 'No.' I said: 'One-third?' He said: '(Give) one-third, and one-third is a lot. It is better to leave your heirs independent of means, than to leave them poor and holding out their hands to people