not know you're born

not know (one) is born

To be unaware of or blind to one's own good fortune or ease of life. Kids these days don't know they're born, being able to do everything with a tap of their phones. Families in this country complain about their life, and then they sit down to watch TV in a warm house after a decent meal. I tell you, some people don't know they're born.
See also: born, know, not
Farlex Dictionary of Idioms.

not know you’re ˈborn

(British English, spoken) not realize how easy your life or situation is compared to other people’s: Young people today don’t know they’re born. Life was much harder when I was a child.
See also: born, know, not
Farlex Partner Idioms Dictionary
See also:
  • not know (one) is born
  • not know you are born
  • not know if (one) is afoot or on horseback
  • be in a world of (one's) own
  • be, live, etc. in a world of your own
  • in (one's) own (little) world
  • in a world of (one's) own
  • in a world of own
  • in one's own world
  • live in a world of (one's) own