Unexpected Animal Rescue

Our house has always been the place that people will bring injured or sick animals - birds that have flown into windows, young hedgehogs who are too small to survive the winter... and then animals just seem to turn up by themselves - feral cats in need of a wild area to give birth, escaped ferrets, even an escaped budgie many years ago. We've only ever taken in a few animals on purpose as companion animals - pets - a couple of rescued rabbits, one which then gave birth, a couple of cats. My parents have never asked for help from anyone - they're more likely to be found taking a neighbour's rabbit to the vet to be vaccinated or spayed than expecting others to help them out. But recently they've had to pay out a huge amount to have feral cats neutered and spayed*, an unbelievable amount to have a few unwell animals put to sleep and others to be vaccinated against diseases such as myxomatosis.

With a number of kittens arriving a few months ago (and who will soon also need to be neutered and spayed*) the cost of feeding the animals (and then looking for new homes for them) has obviously risen. So I'm looking to do some fundraising for them, to help with the food costs and because they've never asked for help from anyone and aren't elligible for reduced costs for neutering and spaying* from animal organisations. They're the kind of people who will just do what needs to be done and help any animal (human and non-human) if they need it.

*stopping an animal from doing the natural thing of reproducing feels awful, feels like you're trying to "play god". But with so many animals already in need of loving homes having been domesticated and who would struggle in the wild, with so many ferals being persecuted or rounded up and taken to overcrowded shelters to wait for homes or be put to sleep and with so many pet shops and breeders still making money from breeding more and more animals, despite the numbers already struggling out there, what other option do we have?

Thanks for looking and thanks in advance if you're able to help. The money raised here will go towards taking the kittens to the vet in the next couple of weeks and the remainder will go towards a bulk order of food I'll be doing. Thanks again!