What became of King Saul's eldest daughter?

       Merab (I Sam. 14:49; 18:17, 19), King Saul's eldest daughter, who had been promised to David for his prowess in slaying the Philistine Goliath. But Merab was not given to David as had been promised (I Sam. 17:25). In the meantime David was entertained in court and received such adulation from the crowd that King Saul became jealous of him.
       For the hand of his daughter Merab he incited David to more dangerous deeds of valor against the Philistines. By this time King Saul's other daughter, Michal, had shown a fondness for David, and matters were complicated.
       Merab finally was given to Adriel, the Meholathite. The passage in II Sam. 21:8 which seems to designate Michal rather than Merab as the mother of the five sons of Adriel, is thought by scholars to be
a scribal error. These five sons, along with the sons of Saul's concubine Rizpah, were put to death and their bodies were left on the gallows for several months until the rains fell.
       Scholars assume that Merab died comparatively young, leaving her five sons, who were cared for by her sister Michal. In later years they became identified as Michal's own children, when in reality they were Merab's children.