1 Kings 1:28

1 Kings 1:28King James Version (KJV)
28 Then king David answered and said, Call me Bathsheba. And she came into the king's presence, and stood before the king
An American English Bible
With Old Testament based on the Greek Septuagint

28 Then King David said: 'Call BathSheba back in. 'So she came in and stood before the king.

This is what I think.
Bathsheba and David had a long history this may have been used when his son set up his own kingdom at this time which David is now aware of. David committed adultery with Bathsheba and then after finding out she was pregnant with his child made a plan to have her husband die and try to get away with it by marrying her after his death and planning to keep all this a secret but his family may have known and his son may have used this to lead people away from him being their king. People of the world are going to use every trick to get what they want. Bathsheba was her king and also her husband. The child she was pregnant with die at birth as the Lord had the prophet tell them but they turned back to the Lord and served Him. Bathsheba at this time was one of the view people he could trust. There comes a time when you need to talk with those you trust to find out where you go next or what you need to do next. To get his kingdom back David may have had to have a civil war because of those of his kingdom serving his son and seeing him as king and no longer accepting David as king.