The sum of $6 + 6$ is:

$6 + 6 = 12$

Would you like more details or have any other questions?

Here are 5 related questions you can explore:

1. What is $6 \times 6$?
2. How would you subtract $6$ from $12$?
3. What is $6 \div 6$?
4. If you add $6$ twice to $12$, what do you get?
5. How do you calculate $6^2$?

Tip: Addition is the most basic arithmetic operation and is a great foundation for more advanced topics like multiplication and algebra.