Cat Peeing on puppy pad?

[Georgeisbad]

So, my son is having major issues with his 3 cats since his wife left him. One of them started pooping outside the box. The other has the runs and would go in the box but then finish outside the box. Took the one he thought was having the problem to the vet and had its anal glands checked. All was fine. Brought the cat home and left again. When arrived back home, one of them had the runs and pooped by the water dish.

I suggested laying down some puppy pads incase they have the runs and now one has urinated on the pad???

He is about at wits end now. I hate to say it but he may have to surrender one to a shelter. The litter hasn't changed. The food hasn't changed. They don't go outside.
It seems like they can feel the stress he is under since his wife left him.

Any suggestions

[Sniper1]

Hi just wondering how many litter trays your sons cats have its generally a good idea to have one per cat and one spare and always clean the tray as soon as you see its been used and also bear in mind your sons wife hasn't just left him she's left the cats too so a major life change for them in.many ways as well they may take time to adjust