'Amr bin Shu'aib (May Allah be pleased with him)on the authority of his father who heard it from his father reported:
Messenger of Allah (ﷺ) said: "He is not one of us who shows no mercy to younger ones and does not acknowledge the honour due to our elders".[At- Tirmidhi and Abu Dawud].
Arabic/English book reference: Book 1, Hadith 355