It's Potter's Son-in-Law that visits the 4077th. However, in the season 4 finale The Interview, Potter tells the reporter "I miss my wife, of course...miss my son, daughter-in-law. I have a new baby grandchild. I haven't seen her. I'd like to."
In "Mail Call, Again", it is established that Col. Potter has only one child which is a son. In this one, he has a married daughter.
Given the level of Charles' snoring, it would likely indicate he has sleep apnea, which would mean he would not be well rested either.
Father Mulcahy says he's seen the 6th commandment take quite a beating when he's talking with Col. Potter about his son-in-law's infidelity. The 6th commandment is "thou shall not kill". Father Mulcahy should have mentioned the 7th commandment which has to do with adultery.
When his son-in-law arrives and Potter searches his tent for the picture frame a federal tax manual from 1958 is seen on his bookcase despite the war ending in 1953.
Bob has a long, pointed collar that drapes over his jacket. This, along with his hairstyle, would not be in fashion in the 1950s and would be more appropriate in 1983 when the episode first aired.