What are the common problems you face with your dear cats?

My one cat stinks. She farts and it stinks, she poops and it stinks, real bad. I don't have that probem at all with my other cat. I have tried all different foods and had her get a check up at the vet. Everything is normal, she just stinks. She smells like she eats out of dumpsters but she is an indoor cat, so I don't get it. One thing is she doesn't cover her stuff up, I know that. lol

I have a 16 year old cat that is prone to skin sbcesses. He isn't fighting, he is indoor.