Hi Wendy, I am immediate engaged by the lovely and loving simplicity of your poem. You have conveyed the love you have for your sister and how much it means to you. You miss her and want her back. In returning you hope to loves you as much as you love her.
I think perhaps she has passed away.
My Sister's, Sister
She has a new sister who writes poetry
A poet I will never be
I am writing this poem as a plea
That maybe she will contact me
I know she doesn't like poems that rhyme
So I doubt very much that she'll like mine
I hope this shows how much I miss her
Oh but to be my sister's sister