That he asked Anas: "Did the Messenger of Allah [SAW] dye his hair? He said: "His gray hair didn't go far, it was only a little at his temples." (Using translation from Nasāʾī 5086)
أَنَّهُ سَأَلَهُ هَلْ خَضَّبَ رَسُولُ اللهِ ﷺ قَالَ «لَمْ يَبْلُغْ ذَلِكَ إِنَّمَا كَانَ شَيْءٌ فِي صُدْغَيْهِ»