This sample note is based on the Template for a Sympathy Note: When You Knew the Deceased. If you weren't acquainted with the person who died, see the template and sample for that situation. For more general information on this topic, see What to Write in a Sympathy Note.
I'm saddened by the loss of your sister Jan. Know that you have my deepest sympathy.
One of my favorite memories of Jan is her big laugh -- I can still hear that laugh when I close my eyes. And I also recall how she could never keep a secret when she got excited about one. Of course, even after spilling the beans about Todd's top-secret 75th birthday surprise, she won her way back into my heart with that big laugh -- that, and her irresistible banana nut bread.
I hope the passage of time will help ease your sadness and leave you with happy memories. In the meantime, take good care of yourself and know that I'm sending healing thoughts and support your way.
With my love and sympathy,