Kissing a child's cut/bruise 'better'

Some ways that I have seen parents make use of the placebo effect to help their children feel better is kissing their child's cuts/bruises/injuries. I have seen it countless times with lots of my relatives having small children. The child will play, fall down, and start crying right away. The child would then cry and walk towards their parents (usually mom) and the mom will 'kiss it better'. Immediately after getting the kiss, the child will stop crying almost instantaneously. I would say I probably experienced the same placebo effect when I was once a small child. The beliefs and values involved was the fact that you felt loved when you got a kiss on your cut/bruise and that once you got that, you knew the pain would stop right away. It's like as if the kiss is a remedy/cure to fix the problem, and because you got one, you knew the cut was no longer a problem (you would forget about it right away)