I am a 16 year breast cancer survivor and those pink ribbons represent HOPE..and CURE...and FAITH....and SUPPORT....and I know that I am a part of a group of women and men, that I've never met, where there's an unspoken bond.....Bring on the PINK......I am thankful for every pink ribbon I see...
People handle things differently, so knowing your sister is a very private person, and having lost one sister (of which I'm so very sorry), If you are unsure, maybe you could ask your sister how she would feel about it...
Wishing you both the very best...Stay positive and keep the faith......
San
FL