From Sahih Bukhari (Hadith 6978):
Narrated 'Amr bin Ash-Sharid: Abu Rafi' said that Sa'd offered him four hundred Mithqal of gold for a house. Abu Rafi ' said, "If I had not heard Allah's Messenger (ﷺ) saying, 'A neighbor has more right to be taken care of by his neighbor,' then I would not have given it to you." Some people said, "If one has bought a portion of a house and wants to cancel the right of preemption, he may give it as a present to his little son and he will not be obliged to take an oath
Reference: Bukhari 6978