Can't see the clip I want in picture in picture

Hello, I just started using Premiere Elements and I'm trying to do a picture in picture, except the small video which needs to be on top is behind the video I'm using as the background, so I can't see it - all I see is my background video. How do I bring the PiP video to the front? I plan to have two videos overlaid over the background, if that's important.

Thanks!