At least several children were killed. You’re missing the point though. A targeted attack means you want to attack a single individual and know exactly where, how, and when to attack. Israel just pressed a button and blew up a bunch of pagers without actually knowing who they would hurt.
Israel has been trying to assassinate Nasrallah for a very long time. He was one of the few figures in the region who actually stood up to them and didn’t run scared or submit to them. I don’t see any way where Nasrallah would have voluntarily left, no matter how credible the threat. If anything he likely would have used this information to prepare Hezbollah for his death to make sure the fight goes on. Hezbollah is still inflicting Israeli casualties even after Nasrallah and so much of their senior leadership has died. Time will tell if these plans are enough though. I hope they are, for the sake of the Lebanese population.