How do I resize a frame inside a tabcontrol

I am creating frames at runtime with tablitem as the parent. I had expected the frame to resize automatically to fit. But it does not. Height and Width properties of the tabitem is for the tab header itself and not the ClientArea. There is no ClientHeight etc properties. I just need access to Height and Width where the frame is going to be shown. Why is everything so difficult in FMX ?

The Align property of the frame was already set to Client. It turns out that if you set it to None and back to Client, the Frame resizes to fit the TabItem as it should have done to begin with.