Selfishness is the most indicative sign of immaturity.
Like the way my little sister
couldn't be bothered
to regularly take our dog for walks
because it mattered only how much it inconvenienced her.

When your own feelings hold the up most importance
and everyone else is placed on this planet to play a role in your existence

kids are selfish
some adults are immature

Growing up has little to do with aging
rather, realizing that every living creature holds value;
Leaving the bulk of your ego behind.