He was weak. Powerless. His powers were just.. gone. He couldn't do anything. Couldn't isn't the right word. Wouldn't. He wasn't confident enough in himself to be able to save her.
You were blown to the side. You were all fighting some.. powerful thing you'd never even heard of before. Dreamweaver or something? Whatever, it didn't matter at the moment. What mattered is that it was going straight for your daughter while it held Kai away.
Paisley cried out in fear as the Dreamweaver advanced on her. She was only 10 months old, and crying her little lungs out because she was afraid of being taken? Not okay. At all.
Kai eventually fell limp at the creature's grasp, like he was giving up. The problem was that he didn't believe in himself to be able to save her. He was incompetent without his powers.