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
john m jr and sally doe
John Doe on behalf of the minor John Doe, Jr. Or John Doe as guardian of the minor John Doe, Jr.
The name followed by Jr For example: John Doe 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.
This is not the way these naming conventions are used. That would never be a John Doe Jr II. John Doe is the first person in a family to have that exact name. John Doe III is the third person in the family to have that name. John Doe, Jr., is the son John Doe; he may NOT choose to be Sr even after the older John Doe has died. Depending on the history of the family, the person being called John Doe, Jr, could be the fifth person (or some other number) in the family to be named "John Doe," and therefore could also be called John Doe V. If that were the case, John Doe, Sr., could also be called John Doe IV. But you NEVER mix the Jr/Sr/II/III naming with numbering at the same time. II is ALWAYS when naming after a relative like an uncle or grandfather and a Jr NEVER becomes a II nor does he ever become a Sr.
Doe, John C Sr Doe, John C II
The etiquette for the groom's parents who have different last names would be: ... to John Doe, Jr. son of Mr. John Doe and Mrs. Mary Smith .....
Naming people "Sr." and "Jr." is a separate system from naming them "Second," "Third," "First," etc. Commonly, John Doe, Jr. can drop the "Jr." from his name after John Doe, Sr. dies, but he does not have to. For example, Sammy Davis, Jr., the famous black entertainer, continued to use "Jr." for many years after his father, Sammy Davis, Sr., died. He did, eventually, call himself simply, Sammy Davis. Naming people "I," "II," "III," etc. is a completely separate system and does not even require that III be the son of II. John Doe III could be the son of Jason Doe, and the nephew, younger cousin, or other relative of John Doe II, as long as both are recognized as being in the same family. The numbering does not change when one of them dies. John Doe IV, the son of John Doe III and the grandson of John Doe II, will always be John Doe IV, even after I, II and III have died. He may as a matter of convenience, choose to drop the number, or, if he has a son named John Doe V, he might choose to be John Doe, Sr., to his son's John Doe, Jr.
To write Jr. (for junior) or Sr. (for senior), you would include the abbreviation after the person's full name. For example: John Smith Jr. or Jane Doe Sr.
* 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.
In most cases the form will have a space for a suffix. In it you would write Jr, or Junior. The most common way to express the name is: John J. Doe Jr. Most people do not spell out the "junior" since the spelling on the birth certificate is your legal name.