The Prophet ﷺ said, "The truest of dreams are those seen in the last hours before dawn."
حدثنا قتيبة حدثنا ابن لهيعة عن دراج عن أبي الهيثم
عن النبي ﷺ قال أصدق الرؤيا بالأسحار
No references are available.
[Its isnad is daif] Ahmad narrated it (29/3) from the hadith of Ibn Lahia through the same route, and he explicitly stated that he heard it directly, and Amr bin Harith corroborated him (Ibn Hibban, hadith 1799, and Hakim, 4/392, who graded it sahih, and Dhahabi agreed with him). Darraj from Abu Haytham is daif, as mentioned previously at 2033.