It also helped that my client was crazy-organized. She sent a color picture of the design with her shirts (which were washed and smelling extra fresh) and took about 0.4 seconds to pick her coordinating fabrics for sashing and backing.
Incase you are wanting to make one for yourself, here are some numbers you might find handy:
I used exactly 3 yards of heavyweight iron-on interfacing for the back of the shirts (12 total squares, 13.5" wide).
1 yard of the navy sashing 3" wide
2 yards for the yellow borders 5" wide
4 yards for the pink backing + cornerstones (3" squares).
I used a navy binding from my stash since there wasn't enough of the calico remaining. My rule of thumb in binding colors - frame your art! I originally thought about using the yellow to blend with the borders but my instincts told me otherwise and I'm glad I obeyed. The navy looks much better on the front and the back than the yellow would have. Whew, close one!
Totally random, but have you ever seen someone eat a tomato like an apple? My youngest girl appropriately enjoyed our first tomato of the season.