The Messenger of Allah (ﷺ) sent ahead some boys from Banu AbdulMuttalib on donkeys on the night of al-Muzdalifah. He began to pat our thighs (out of love) and said: O young! boys do not throw pebbles at the jamrah till the sun rises.

Abu Dawud said: The Arabic word al-lath means to strike softly.
Sunan Abi Dawud Book 11, Hadith 220