What is the age gap between you and your partner?

Hi all 😊 I'm 37 and my boyfriend is 48. The last month there has been 3 people refer to me as his daughter! 😬 I don't take it seriously, and it doesn't bother me, though it makes him feel uncomfortable and I can totally understand why. I would hate if someone mistook me as his mum! 😐
I'd never really thought much about the age gap, and am curious to know what sort of age gap you lovelies have between you and your partner?