<human>: My girlfriend is a barista in a Catholic hospital coffee shop. Near the end of her shift a couple of 12 year old kids rolled in and snatched her tip jar. 

She chased the kids outside and snatched one of them and called the police (the hired mall cops at the Catholic hospital couldn't care less, one even just walked away from the situation). 

When the police arrived they contacted the kids parents. They came in strung out and intoxicated. The kid that got away had all the tip money. Since the caught kid had none of the money and was a minor. All the police did was make the 12 year old come in an apologize to my girlfriend. During which the father snickered and laughed, making the comment "look, at least your change is still here!". Only the cash was stolen. 

Post apology the parents hung out in their car until the police cruiser left. After which the 12 year old got out and walked in one direction. While the parents drove off in another. 

We found out that the kids both live within 2 blocks of the hospital. Coincidently WE live 3 blocks from the hospital. I am certain I can find these delinquents out and about. 

What is a legal way I can teach these kids a lesson? Or should I just let it go?

Can you succinctly summarize the text in 1-3 sentences?
<bot>: gf had her tip money stolen by punk twelve year olds. Who got away with it after their parents and the authorities gave no fucks. How can I teach them a lesson?