Narrated Kuraib:
Ibn `Abbas said, "The Prophet (ﷺ) slept till he snored and then prayed (or probably lay till his breath sounds were heard and then got up and prayed)." Ibn `Abbas added: "I stayed overnight in the house of my aunt, Maimuna, the Prophet (ﷺ) slept for a part of the night, (See Fath-al-Bari page 249, Vol. 1), and late in the night, he got up and performed ablution from a hanging water skin, a light (perfect) ablution and stood up for the prayer. I, too, performed a similar ablution, then I went and stood on his left. He drew me to his right and prayed as much as Allah wished, and again lay and slept till his breath sounds were heard. Later on the Mu'adh-dhin (call maker for the prayer) came to him and informed him that it was time for Prayer. The Prophet (ﷺ) went with him for the prayer without performing a new ablution." (Sufyan said to `Amr that some people said, "The eyes of Allah's Messenger (ﷺ) sleep but his heart does not sleep." `Amr replied, "I heard `Ubaid bin `Umar saying that the dreams of Prophets were Divine Inspiration, and then he recited the verse: 'I (Abraham) see in a dream, (O my son) that I offer you in sacrifice (to Allah)." (37.102) (See Hadith No. 183)
Narrated Ibn `Abbas:
One night I slept at the house of my aunt Maimuna and the Prophet (ﷺ) slept (too). He got up (for prayer) in the last hours of the night and performed a light ablution from a hanging leather skin. (`Amr, the sub-narrator described that the ablution was very light). Then he stood up for prayer and I got up too and performed the ablution in the same way and joined him on his left side. He pulled me to the right and prayed as much as Allah will. Then he lay down and slept and I heard his breath sounds till the Mu'adh-dhin came to him to inform him about the (Fajr) prayer. He left with him for the prayer and prayed without repeating the ablution. (Sufyan the sub-narrator said: We said to `Amr, "Some people say, 'The eyes of the Prophet (ﷺ) sleep but his heart never sleeps.' " `Amr said, "'Ubai bin `Umar said, 'The dreams of the Prophets are Divine Inspirations. Then he recited, '(O my son), I have seen in dream that I was slaughtering you (offering you in sacrifice).") (37.102)