We adopted a rescue kitten 5 weeks ago. I noticed the kitten had loose poop but didn't think anything of it. Over the last 5 weeks the kitten has got diarrhoea. We have an appointment with a vet on sat. We feed it science diet and fancy feast kitten as the person I adopted from said that's what she eats. But she farts all the freakin time and her poops are deadly. Any idea why this might be happening? We have another cat and never had any issues like this. Both cats are indoors.