How to delete just the container.

I have a project where most of my controls (there are many) are placed on a background Rectangle control that takes up most of the window. The Rectangle control is a container for the controls within its bounds. I would like to delete the Rectangle control but leave behind the controls that were on it. It won’t do this because of its container status, all the other controls disappear too. I’ve tried sending it to the front, then deleting. Didn’t work. Resizing it first (so it won’t encompass the other controls) does not work because many other controls are locked to it to resize also. I’m kind of stumped. I’m probably missing something very basic here, but I can’t figure out how do such a simple thing. I’m on a mac.

This probably isn’t the best way to do it, but I always temporarily move all of the contents off of the container manually (usually to outside of the window area), delete the container, and then move the items back into place.