Genesis 25:1 - 27:46
KJV - 1 Then again Abraham took a wife, and her name was Keturah. 2 And she bare him Zimran, and Jokshan, and Medan, and Midian, and Ishbak, and Shuah.
For follow-up discussion and general commentary on the topic. Comments are sorted chronologically.
I have an observation to make.
Abraham left Sarah and went with Isaac to the land of Moriah (Moriah in Syriac means Lord) to comply with the direction of the Lord to sacrifice Isaac (Gen 22:2) without informing Sarah anything about Lord's directions. As per the subsequent direction of the Lord, he saved the life of Isaac. And Abraham sacrificed a ram 'provided' by the Lord (Vide Gen.22:8, Gen.22:13 &14) Then Abraham (and Isaac) did not go back to Sarah but he (they) went and stayed at Beersheba. Sarah died in Kirjath Arba (Hebron) in Canaan and Abraham came to the place where Sarah died to morn and weep for her.Gen.23:2)
Thus Sarah and Abraham lived separately ever since the 'sacrifice' and it appears, they never met afterwards.