Gilda

otosan (dad)
okasan (mom)

I was taught that [title] [lastname] is how you address every adult until asked to do otherwise, regardless of relative age. I still address Dr. KGB in that manner because she's never asked me to use her first name, and will continue to do so.

The exception is with students, because that's a superior/subordinate relationship, in which it's appropriate for the superior to use a first name, regardless of age.

When dating it was always Mr. or Mrs. Lastname, except for my last boyfriend's mom, who insisted I use her first name because Mrs. Lastname or Ma'am made her "feel old". It made me undomfortable, but I did it, though I really can't understand the reasoning. It's a sign of respect and indicates that a woman is married, and has nothing to do with age. I was getting called Ma'am when I was 21 and it didn't bother me, even though it was the wrong title at the time.

I told KGBoy he could call me Gilda, but he continues to call me Dr. Nakamura, which is fine with me. It seems to make him uncomfortable to do other wise--I'm Dr. Nakamura, Grace is Mrs. Nakamura, and Sissy is Sissy. I don't know why she gets to be called by her first name, but that's how it's worked out.

I sometimes think I'm an anachronism, and that the US has abandoned the basic rules of courtesy.

The basic rule of thumb is that you call others by whatever name was used when they were introduced or when they introduced themselves. It's hard to go wrong with that.

Gilda