Here's an example scenario: You are at a public swimming pool. Fairly large outdoor complex. You are 12. You have gone to the pool with your family and they have met up with another family there. The other family has a toddler of about 18 months who is running around. Every time the toddler wanders, the 12 year old is told to go retrieve the toddler and bring him back. Toddler wanders off to the deep end of the big pool and the 12 year old is again told to get the toddler. By this stage 12 year old is getting sick of it and walks at a normal pace, doesn't run. Parents tell the 12 year old to hurry up so the toddler doesn't fall into the pool. 12 year old doesn't speed up. Toddler gets to the edge of the pool but no further.
12 year old retrieves toddler and returns them. 12 year old is told off for not running as fast as they can to get the toddler and it would have been her fault if toddler fell in. 12 year old protests that it is not her child to have to chase and says the parents shouldn't have had children if they didn't want to look after them. Parents of 12 year old say that it's fair for the parents to get a break so 12 year old should chase the toddler.
Who is wrong? 12 year old or 12 year old's mother?