meyert

I am working on a memory quilt for my sister. I have started the Jacob's Ladder pattern (that was my nephew's name) with his jeans and pieces of shirts but I modified it a bit to be able to insert the logos from his favorite tee shirts. When I sew them together the big tee shirt section gets "floppy" as you can see in the picture. The diamond shape ones are the ones that bother me.

I have several others to do so I would like to find a way to avoid as much of the floppiness as I can. The shirts have been interfaced - lightweight interfacing.

Should I have used heavier interfacing? Is heavy starching what would help with this?

Any ideas?

Please let me know

Thanks
Teresa