Inside Envelop?

Hi everyone. I posted this on the BHB boards but didn't get many responses.

How are you addressing your inside envelope? Are you just using the persons First Name or the name you call them by (like nicknames or Aunts and Uncles) or are you doing it formal with Mr. and Mrs?

TIA

someone just posted this website that shows the 'proper way of doing it' hope it helps

http://www.stylishaddressing.com/etiquette.htm

someone just posted this website that shows the 'proper way of doing it' hope it helps

http://www.stylishaddressing.com/etiquette.htm

i did

outer
mrs & mrs x

inner
joe & sue x