Since Leo started
The pattern is made to fit 6 weeks to 3 months, so I added several inches to the bottom and two to the sides so that it might fit my big boy all winter. He is 6 months, 19 pounds and 28 inches long now.
I made two other alterations to the pattern—continued the bias tape to cover the edge of the under panel as well (piece B) with a mitered corner at the point (she just says to zigzag stitch that edge), and I used six snaps instead of velcro. Unfortunately I didn't think to add interfacing to the snap locations before I joined the outer fabric and flannel, so we have to be a little bit gentle when we unsnap it. Also, I should have put the first snap all the way up at the point. Wish the snaps were not white, but that is all they had at the store.
Much cuter than the store-bought fleece sack Louisa wore!