Ahmed bin Suliaman أحمد بن سليمان · The Book of Presents

"I want to give this son of mine a slave as a present, and if you think that I should go ahead with it, I will go ahead." The Messenger of Allah said: "Have you given a present to all your children?" He said: "No." He said: "Then take (your present) back."

"Ask the Prophet to bear witness to what you have given to my son." So he came to the Prophet and told him about that, and the Prophet did not want to bear witness to it.