Do I look like my father´s girlfriend???

My cousin was having a birthday party and he had a new girlfriend who I had not met.  I arrived with my father, mother and my boyfriend. For some reason my boyfriend and my mother walked far behind me and my father so we arrived before them and we were greeted by my cousin and his new girlfriend. We shook hands and she said:
- So you are the uncle and aunt?
- Eh, no I am his daughter.


Come on....Really!? There is an age difference of 37 years!
I did not take that as a compliment!!!!