We're so happy to welcome you to the family! I wanted to share an open letter to my future daughter in law.A "thank you for joining" membership letter should include a personalized greeting to the new member. Use the member's first name in your salutation. Here are 10 things your welcome letter or email to new members must include plus a template that can be customized for your organization. A good welcome letter acts as a travel guidepointing members to key resources, highlighting benefits, and outlining simple next steps. 1. Enter the date at the top of the letter. Dear Daughterinlaw,. Today, you enter our home with new dreams and hope. The California Department of Public Health is dedicated to optimizing the health and wellbeing of Californians.