How to differentiate 3rdPersonCharecter and its child?

You don’t need to, it sounds like you’ve done it fine. Just make sure the end screen casts to your main player before trying to show the end.

EDIT: Like this:

You can’t cast to third person, because they’re all coming from third person. So, you have to check if you’re one of the enemy types, if you’re not, you must be the third person, and so you die…