sRectangle resizing trouble using corner handles.

I am trying to resize this sRectangle shape by pulling at the white, corner handles but it won’t stay square.
If you mouse-over the edges you’ll find that there are: corner handles, top handles and side handles that light up white to indicate their presence.
I’m wondering if anyone knows if I can link the Width and Height sliders in the sRectangle Inspector?
I’m trying to avoid key-framing the sliders individually.
I’m surprised that there isn’t a “Size” or “Link Width/Height” option in the Inspector.
If you mouse-over the edges you’ll find that there are: corner handles, top handles and side handles that light up white to indicate their presence.
I’m wondering if anyone knows if I can link the Width and Height sliders in the sRectangle Inspector?
I’m trying to avoid key-framing the sliders individually.
I’m surprised that there isn’t a “Size” or “Link Width/Height” option in the Inspector.