Frame heights - not staying equal

[rogiller]

I have an issue with some frames that I can not resolve.

 

I have 3 frames side by side. They contain stretchable textfields. The frames are in a group and set to stretch relative to tallest object. I want the frames to be the same height no matter what but I can't seem to achieve this. I have the frames set to remove line when blank so that they shrink if there are textfields that remove line when blank. The frames shrink but they do not stretch as high as the tallest frame in a group. I realize this is because no frame is stretching so no other frame in the group is compelled to stretch either. How can I keep three frames side by side to have equal heights?