Old sick outdated kittycats, I want to permapet them....

[Issybella Quintessa]

But they are sick and outdated and only give me their ID number when I click on them. How do I fix this? I just want to make these two into perma pets. These were the first kittycats I ever had and back then I was too poor to feed them so they got sick and I just took them into inventory. I can't seem to cure them. I got the meds for them but they did not work. Any help? TY