When King David was very old, he could not keep warm even when they put covers over him.
References for 1 Kings 1:1
So his attendants said to him, “Let us look for a young virgin to serve the king and take care of him. She can lie beside him so that our lord the king may keep warm.”
Then they searched throughout Israel for a beautiful young woman and found Abishag, a Shunammite, and brought her to the king.
References for 1 Kings 1:3
The woman was very beautiful; she took care of the king and waited on him, but the king had no sexual relations with her.
Now Adonijah, whose mother was Haggith, put himself forward and said, “I will be king.” So he got chariots and horses ready, with fifty men to run ahead of him.
References for 1 Kings 1:5
(His father had never rebuked him by asking, “Why do you behave as you do?” He was also very handsome and was born next after Absalom.)
References for 1 Kings 1:6