My future mother-in-law shares a home with the man she is dating and my future brother-in-law (over 18) lives with them as well. Also, we are only doing single envelopes. How do I address their invite?
Would it be
Mrs. (mother in law)
Mr. (boyfriend)
Mr. (brother in law)
or
Mrs. (mother in law)
Mr. (boyfriend) and Mr. (brother in law)
Or should I just send my brother in law a separate invite or do something else entirely?