Mrs. Greta & Mr. Neal Featherston, Jr.
You would address for a Junior: Mr. & Mrs. John Jr., or, Mr. John Jr., and Mrs. Sarah Smith.
The name followed by Jr For example: John Doe Jr
Mr & Mrs James Angstrom Jr.
Example : Mr & Mrs Edward J. Flynn Jr.
When the husband is a 'Jr.' and your letter is formal and not private you would address it (example:) Mr. John Doe, Jr., and Mrs. Jane Doe or it is still fine to put: Mr. & Mrs. John Doe, Jr. If you know the couple as friends then in the letter or note you can just put their first names and drop the Jr.
* Depending on the individuals status it would be: Mr. & Mrs. John Doe. If the man was a doctor then is would be: Dr. & Mrs. John Doe. If the woman was a doctor and her husband wasn't then it should read: Mr. John Doe & Dr. Jane Doe or (some professional women keep their maiden name and take their husbands name it would be: Mr. John Doe and Dr. Jane Smith-Doe.
mr ans miss or.... for mrs is madame. mr ans miss or.... for mrs is madame.
There has been a small change in social convention over the past decade. The appropriate address, in traditional circles would be: Mr and Mrs John Doe Jr. However, it is now an acceptable address, outside of more traditional societies to address your letter as John and Mary Doe Jr. When there is a hyphenated name, such as when a spouse has elected to retain her married name, the form would be: Mr. John Doe Jr Ms. Mary Smith-Doe, Jr. Address
I would address it to Mr and Mrs David Keys. For the salutation I would use Dear Mr and Mrs Keys.
Mr. and Mrs. John Smith III
At the end of the name Mr. and Mrs. John Smith, Jr.
Mr. and Mrs. James Bitner III