Dear Mike,
Thank you for your letter. It was great to hear from you!
You say you're having a problem in communication with your older sister. Well, I know what you feel because I used to have a rocky relationship with my brother, but luckily we have found the way to communicate.
I think you should show your interest in your sister's life but please remember to be tactful and avoid calling her bad names. You should also offer your sister help and support.
I hope my advice will help you.
Keep in touch.
Best wishes,
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