"What about a litter box? Litter?" Peter might not have ever owned a cat, but he at least knows the basics of what a cat needs. "We're going to have to make sure he has a place to use the bathroom."

Probably the most important part, but still, there's more.

"What about something to scratch? Or toys?" Peter frowns, thinking. "We might be able to make something for him." They still needed to worry about the litter box and litter, though.