Yes Cindy just disapeared on the way to the beach camp with the tail survivors while Sawyer was on the strecher and pulling him up the "wall" for lack of a better term, she disappeared.. Then she shows up while Jack is in the cages with the to kids Zack and Emma (I think) and said "We're here to watch" Then we see her and the kids again in the others camp when John Locke was with them and supposed to kill his father.. That was the last time we saw them I think

__________________
Please don't give up, Des. Because all we really need to survive is one person who truly loves us. And you have her. I will wait for
you. Always. I love you, Pen

DESMOND: I love you, Penny. I've always loved you. I'm so sorry. I love you!
PENNY: I love you too.
DESMOND: I don't know where I am, but--
PENNY: I'll find you, Des--
DESMOND: --I promise--
PENNY: --no matter what--
DESMOND: --I'll come back to you--
PENNY: --I won't give up--
BOTH: I promise. I love you.