Habib bin Abi Thabit narrated that I was with Ibn Umar (may Allah be pleased with them) when a man from among the Bedouins came and said, "I had gifted a she-camel to my son for as long as he lived, and she bore many camels." So Ibn Umar (may Allah be pleased with them) said: "That she-camel belongs to him, whether he lives or dies." The man said: "I had given it as charity." Ibn Umar (may Allah be pleased with them) said: "If that is the case, then you cannot take it back under any circumstance."
Hadith Referenceمسند الإمام الشافعي / كتاب صدقة التطوع والهبة وصلة الوالد والأخ المشرك / 1054
Hadith Takhrijاسناده صحیح اخرجه البيهقي : 174/6 - وفي المعرفة السنن والآثار له (3794) - وعبدالرزاق (16877)، (16879) وابن أبي شيبة (22616)۔