Pam - your quilt is SPECTACULAR but do not put that much pressure on yourself for the post-op period. I am a 17-year survivor of a malignant brain tumor, and a 13 year survivor from acute leukemia.
I always found that after the initial treatment of each cancer it took a good 6 months to get back to my previous energy and attention span level. I couldn't even read the novels I had stockpiled to read during recovery. I ended up with mystery novels. Give yourself a break.
Prognosis is very good for most breast cancers, and you should have time to
finish the quilt and present it to your sister at some future date.
Best of luck - Judy