SOUL SISTER: A sister or female friend with whom you share a closeness that no one else understands. A keeper of secrets, always there to help, through thick and thin. Someone who accepts your weirdness and loves you anyway. A best friend for life - the best thing you can have and the best thing you can be. She sees you at your worst, supports you anyway, and celebrates you at your best. Picks up right where the two of you left off, no matter the time spent apart. She knows your heart, so it is easy to forgive any mistakes.