2 Sam. 21:8-9

"But the king took the two sons of Ripah, the daughter of Aiah, whom she bore unto Saul, Armoni and Mephibosheth; and the five sons of Michal, the daughter of Saul, whom she brought up for Adriel, the son of Barzallai, the Meholathite; and he delivered them into the hands of the Gibeonites, and they hanged them in the hill before the Lord. ..."

Things just got worse for Michal. She had despised the rejoicing of David before the Lord (2 Sam. 6:20) and as a result he basically put her under house arrest and denied her children of her own. Then the sons of her sister, whom she had taken under wing and raised as her own, were sacrificed to the Gibeonites. Though Michal was bride to the king, she was still the daughter of Saul, and she showed no fear of the king, instead believing she could get away with anything. Then she paid the price. "But preached ... that they should repent and turn to God, and do works fit for repentance." (Acts 26:20)