It is narrated from Sayyiduna Wathilah bin al-Asqa' (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: "Whoever does not show mercy to our young and does not honour our elders is not one of us."
Hadith Referenceالمعجم الكبير للطبراني / باب الواو / 18449