Oldest son Mike is mentioned in this episode. His college diploma hangs on the wall in Chip and Ernie's bedroom.
Margie claims to a secretary out at the Aircraft Plant where Steve works and that she is just 22 years of age.
The actual name of Margie Milford's fiancee is Jim Johnson. Steve mentions that he has been working in Bolivia on a government project.
This is George Takei's third appearance on the show (first in color).
When Ernie and Uncle Charley initially attend the rehearsals for the show at the school, the opening footage shows the backs of the audience members -- but this is actually a duplicated shot from later in the episode during the the final performance. It's easy to spot in reverse as the extras filmed during this scene are wearing different clothes -- firstly suits and then casual attire. Perhaps the show's film editor needed some establishing shots and chose it from the earlier part of the episode hoping no one would notice?
Here is the full text of the invitation, the British spelling of 'honour' consistent with Sally's English father:
Mr. and Mrs. Charles Frazier Morrison
request the honour of your presence
at the marriage of their daughter
Miss Sally Ann Morrison
Mr. Michael Douglas
at Bryant Park Community Church
on Thursday, the sixteenth of September
nineteen hundred and sixty-five