John Gill Commentary 2 Chronicles 13:2

"Three years reigned he in Jerusalem: and his mother`s name was Micaiah the daughter of Uriel of Gibeah. And there was war between Abijah and Jeroboam." — 2 Chronicles 13:2 (ASV)

He reigned three years in Jerusalem
(See Gill on 1 Kings 15:2),

his mother's name also was Michaiah the daughter of Uriel of Gibeah ;
see (2 Chronicles 11:20) , (See Gill on 1 Kings 15:2).

and there was war between Abijah and Jeroboam ;
and in this chapter is an account of a battle fought between them, not recorded in the book of Kings.