I have a question regarding my recent experience:
I basically would like to know WHO my dad was referring to here...
Little background info for reference first:
(My dad's friend came to our home to fix a furniture in my room and I only met him once before a couple of years ago (my appearance was about the same back then too) but my brother(younger than me) never met him. )
He sees me while talking to my dad and asks "is that your son"? and greets me. (I show no sort emotion nor does my dad)Although I definitely heard him say something back in a mumbled voice but because it was so soft I couldn't tell>

So the guy eventually comes to my room to check it out while referring to me with male pronouns to my dad the entire time and asks me if my SISTER was the one who damaged it.
This is actually where my question lies:
Some time pass and downstairs in the living room and my dad and the guy are talking business stuff at the couch farther from me but I could clearly hear them.
I am just facing my table minding my business (pretending I don't even listen to them) and all of a sudden the guy asks "So who's older your daughter or your son?"
(3-4 seconds pass) and he says: "My (1 second pause) son" and then quickly changes the subject and asks a question to him.
From this information, I would like to know what you honestly make of this, meaning did he refer to me as his son (since the guy was already referring to me as 'he') or my brother (who is actually younger than me) as his son?
The only thing is that created this sister here is that my dad probably introduced me to him referring to me as his "daughter" that time so that's probably the only indication of this 'daughters' existence in the guy's mind? (Or maybe back then he read me as a 'she)