Okay kiddo, let me explain what a dose-response relationship is.
You know how sometimes you take medicine when you're not feeling well? Well, that medicine has a certain amount in it that helps your body get better. This amount is called a "dose."
Now, let's say that you take a small dose of medicine and it helps you feel a little better. But, if you take a bigger dose, it might help you feel even more better! This is where the "response" part comes in.
The dose-response relationship is all about figuring out how much of a certain thing (like medicine) you need to take to get the best response (feeling better). Sometimes you might need a little bit, sometimes you might need a lot - it all depends on the thing you're taking and what your body needs.
It's important to remember that taking too much of something can sometimes be bad for you, so always listen to your doctor or grown-up when they tell you how much you should take.