I can't see your mistake, but I'm glad you caught it in time. My condolences on losing your sister, I know it's difficult. My sister had asked me to help her make a simple one patch quilt for her great-granddaughter, however, she passed away before we could even start. I'm afraid it took me a couple of years before I could start on it and then her DGGD had another little girl, so I figured what's one more quilt, even twin sized. That would be great but she had another little girl. Yesterday I finished sewing the blocks together on the third quilt; as I felt I had to make quilts for the other two girls. I'm sure my DGN will be surprised one day when she gets the quilts, as my sister's fabric is in the second and third quilts as well. Quilting to me has always been healing for me and a way for managing stress. God bless and I know your sister will always be in your heart.