29 As soon as he began to reign, he killed Jeroboam’s whole family. He did not leave Jeroboam anyone that breathed, but destroyed them all, according to the word of the LORD given through his servant Ahijah the Shilonite.

Read 1 Kings 15:29 Using Other Translations

And it came to pass, when he reigned, that he smote all the house of Jeroboam; he left not to Jeroboam any that breathed, until he had destroyed him, according unto the saying of the LORD, which he spake by his servant Ahijah the Shilonite:
And as soon as he was king, he killed all the house of Jeroboam. He left to the house of Jeroboam not one that breathed, until he had destroyed it, according to the word of the LORD that he spoke by his servant Ahijah the Shilonite.
He immediately slaughtered all the descendants of King Jeroboam, so that not one of the royal family was left, just as the LORD had promised concerning Jeroboam by the prophet Ahijah from Shiloh.