Translation offered:
Dear Aunt and Uncle,
I send you our tiny house. Do you remember it? As you can see, we are all fine and alive. Also grandma is smiling from behind. We have received your letter.  Also the newspaper is arrived safely. I believe you: you are living in such a beautiful town and you can’t even look at it.
My best wishes from your dear people of Buchholz.
Your Karl, Lina and Grandma