Do I capitalize s on "son" when it's used casually such as "Say hi to your pa for me, son."?

"Tell your pa I'm here, sonny." or "Tell your pa I'm here, Sonny." (When the boy's name is not Sonny.)

Solution 1:

As noted by Edwin Asworth in his answer, when used in direct address, honorifics are usually capitalized. This applies when they are used alone or as part of a name.

Please help me, Doctor.

Please help me, Dr. Jones.

But as discussed on the website of the Chicago Manual of Style, capitalization of terms in direct address also goes beyond honorifics to encompass virtually any word used in direct address in lieu of a name.

I love you, Father.

Oh, Cutie, look this way!

Hey, Buddy, can you spare a dime?

Excuse me Son, but quit while you're ahead.*

*(Said to me by a judge when I interrupted him. I could hear the capitalization in his tone of voice. I shut up.)

Solution 2:

Some honorifics act as complete replacements for a name, as "Sir" or "Ma'am", or "Your Honor". I don't see why 'Son' or 'Dad' should not be afforded this honour. Essentially, only nitpickers are going to argue the toss if you choose the version that they don't like.