The Prophet (ﷺ) used to pray witr with five and he did not sit except in the last (rak'ah) of them.
Sunan an-Nasa'i Book 20, Hadith 120
← Previous Hadith "Witr is seven and no less than five." I mentioned that to Ibrahim and he said: "From whom did he quote that?" I said: "I do not know." Al-Hakam said: "Then I performed Hajj and I met Miqsam and said to him: 'From whom (did you narrate that)?' He said: 'From the trustworthy one, from Aishah and from Maimunah.'"

Sunan an-Nasa'i Book 20, Hadith 119 Next Hadith → Aishah said: "When the Messenger of Allah (ﷺ) grew old and put on weight, he prayed seven rak'ahs and only sat in the last of them, and he prayed two rak'ahs while sitting after saying the taslim, and that was nine, O my son! And when the Messenger of Allah (ﷺ) offered any prayer he liked to persist in doing so."

Sunan an-Nasa'i Book 20, Hadith 121