Quran 73:17 from Surah Al-Muzzammil on Divine Marvels.
فَكَيۡفَ تَتَّقُونَ إِن كَفَرۡتُمۡ يَوۡمٗا يَجۡعَلُ ٱلۡوِلۡدَٰنَ شِيبًا
English translation: Then how will you guard yourselves if you disbelieve a Day (that) will make the children gray-headed
Transliteration: fakayfa tattaquna in kafartum yawman yaj'alu al-wil'dana shiban