A girl I know from work who is about 13 is causing me a bit of animal-related heartache. I told her when she bought her first goldfish that her tank was too small. I bought her a filter, which she only turns on once a week, and water conditioner, which she doesn't use at all. She only feeds them when she remembers. After the predictable death of two of her fish, she bought another three, despite knowing that the tank was two small for even one (it's about 2.5 gallons).
When they go away, they lock the cat in the garage with a bowl of food and some water. They go away for several days, so the cat has to ration itself, and they have no cooling, so their garage could easily be as hot as 35+ degrees celcius at this time of year.
She had a guinea pig, which recently died. It wasn't neglected but it wasn't well treated either. Her mother has bought her another one, and now they are thinking of also getting a male and breeding.
These are the people who won't buy meds for their cat because they are too expensive. This means that they are not going to be able to afford to neuter a guinea pig after she has had her first litter, so they will have more and more and more and the female will always be pregnant and they won't be able to rehome the babies.
It doesn't matter what I say to this girl. I think she cares, but she lets her selfish desire to have the animals she wants override it every time.