Some online games-for-kids don't allow freeform text, so the game can control what kind of communication is allowed. Others are very heavily moderated. You cou

Some online games-for-kids don't allow freeform text, so the game can control what kind of communication is allowed. Others are very heavily moderated. You could also require parents to identify themselves, I guess, similar to how some financial/banking apps do? Not fool proof, but would raise the barrier for predators to enter.