The Messenger of Allah ﷺ said, "Jibreel kept urging me to take care of the neighbor until I thought he would make him an heir."
قال حدثنا عفان حدثنا محمد بن طلحة عن زبيد عن مجاهد
قال رسول الله ﷺ ما زال جبريل عليه السلام يوصيني بالجار حتى ظننت أنه يورثه
Its isnad is sahih. Zubayd is Ibn Harith al-Yami, a trustworthy narrator, and his hadith is found in the collections of the group. The hadith has already appeared at 24141.