Riyad as-Salihin

'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, who both classified it as Hadith Sahih].