Here are some quotes about sister best friends that I found:

- "Sisters are different flowers from the same garden." - Unknown
- "A sister is a little bit of childhood that can never be lost." - Marion C. Garretty
- "A sister is someone who knows everything about you and loves you anyway." - Unknown
- "A sister is a gift to the heart, a friend to the spirit, a golden thread to the meaning of life." - Isadora James
- "Sisters are like two flowers from the same garden. The sun was created to shine on both of them." - Unknown

I hope these quotes help you out! Let me know if there's anything else I can help you with.