You're a parent and every time you go to the store your child starts yelling and crying and you buy the child a toy. What's going on?

You're a parent and every time you go to the store your child starts yelling and crying and you buy the child a toy. 

• What's going on? Would this be reinforcement (positive or negative) or punishment?

• How can you stop the yelling and crying behaviors? Would this be reinforcement (positive or negative) or punishment?