20He's Got Toys And Games Everywhere
Having too many toys and games can be a sign that he hasn't really grown up.
There's nothing wrong with having a robust collection of action figures, comic books or video games. If he's got a shelf of action figures in their boxes, that's different from having a whole wall or room devoted to his toys. If his whole place looks like it's devoted to his
toy collection, that's definitely a red flag. And, if he has more video games than your little sibling, that's a red flag too.
It can also indicate that he spends more time in the virtual world than the real world, which means he won't have much time for you.