User blog comment:PercyJacksonfan12/The Hundred handed Ones/@comment-3146930-20111112232141

She was upset that their father sent them to Tartarus, so Kronos took over and he kept them down there. While Gaea had the power to set them free, it was the gods that set them free in the end. Plus, Briares works for the gods and seems pretty happy about it, I'm sure he would convince his brothers