<human>: This is a fucking silly issue, but it could lead to bad.

My girlfriend's parents know about me and that we will meet in a month. She just told her dad that I recently turned 19, and he kept saying "18? That's a great age". If he was a typical man, he'd shrug it off as a misunderstanding, but she keeps telling me that if she tells her dad the truth now, he will think that she was lying to him, and that he could do something like not letting her meet me in February.

He is a very complicated character, and when summarized, this just sounds stupid over such a slight misunderstanding. I'm not comfortable with lying about my age.

How can this situation be solved? Any bright minds?

Can you condense the text into three sentences or less?
<bot>: My girlfriend's dad think I'm 18, and we want to make him realize I'm 19 without causing him to accuse my girlfriend of lying.