September 20th, 2012

What did children call their parents?

This is a question that has caused me a lot of consternation. 
Problem: I'm having trouble figuring out how my MC would address his parents in conversation (as opposed to written correspondence.) 
For the present I've oscillated between Mom/Dad and Mother/Father when applicable but Mom/Dad seems too... contemporary. If I could find historical confirmation that this was used informally, that would be fantastic and would eliminate the contemporary feeling (in my mind) but, as I am posting this, I have yet to find that confirmation. Other variations ma/pa, mama/papa, etc. feel appropriate during childhood but what about during adulthood? The story spans approximately 24 years of my MC's life. 

Setting: 1880s-1910s United States of America; rural northern Pennsylvania
(More specifically, agricultural community. Characters in question are of Western European descent, several generations removed from immigration.)

Searches Attempted: (Google) variations on: children names for parents, what did children call their parents, how did children address their parents, names for parents; all Google searches tried on their own as well as with time period tags (late 19th century, late 1800s, early 1900s, early 20th century, 1900s, 1880s, 1890s, etc.); all Google searches re-tried with varying additions of rural, country, agricultural, agrarian, Pennsylvania, lower class(es), United States.   
Also read into etiquette for the time period in question, looked at books featuring child characters published during time period, looked at letters written during time period. (Google Books, public library, (my) University Library website)

The problem with my searches were that the results tended towards upper class usage or gave me Victorian Britain results which cannot necessarily be accurate across the board. It seems to be very easy to find historical details about the upper classes and sketchy details about the lower. 
The story is not a true historical fiction, as there is the addition of a fantastical element (shape shifters), but I've been trying to be as accurate as my research will allow.

Edit
Thanks for the input everyone, I've got a lot to go on now!