Dean writes:

My son, Jacob, is rather rough with our cat, Cleo.  He wants to play with her, but he often pulls her tail or rips whole pieces of fur out from her backside.  What can I do to teach him how to pet nicely?  I'm worried she may bite him one day.

Mr Lady:

Are your cat's shots up to date?

We've taught our kidss 'Give Love' and 'Soft Hands', and that worked for a while, but when push comes to shove, there are just some things your kids are going to insist on learning on their own.  The sooner you come to terms with that, the longer you'll postpone going gray.

My kids did not believe me that the stove was hot until they grabbed it.  They didn't believe me when I told them that mommy's soap is for mommy until they got it in their eyes.  They didn't believe me that the dog really didn't appreciate being drug about by the tail until the dog let them know herself.  They didn't believe me that sockets were buzzy until I had to pry them (and my good tweezers) off of the wall.

I don't mean to say we didn't try to explain these things to them; I can't count how many times I said, "No, hot!" or "Owie!" but at the end of the day, they had to test my theories, they had to find their own way.  They don't really ever stop doing this, but the earlier in life they learn that you have some credibility behind your words, the easier those years are when they test you on really big things.  And I promise you, they have to prove TO THEMSELVES that you're not full of shit.  Sometimes that means letting something unpleasant happen to them.  Kids don't really do blind faith very well past, oh, age 2.

I'd probably say either give Jacob a little smack on the hand every time he's too rough with the cat (because the cats safety is still your responsibility, too) or, if you're not cool with that, just keep telling him no and be ready for when the CAT tells him no, too.  Maybe, just maybe, one little snip from the cat will save Jacob one big snap from a strange dog someday.

BusyDad:

A little blood can do wonders. And a cat can't do much damage. You have the perfect learning tool at your disposal. If you had a medium to large dog, I would proceed directly to Plan B below. Warn little Jacob accordingly and make sure he knows you are warning him. "Jacob, you know what happens when you bother the cat? Cat gets mad and scratches Jacob. OW!" He won't take you seriously. In fact, he'll laugh. But keep saying it. And let him do his thing. He will eventually piss off the cat, and the cat will swipe (I really don't think he'll bite. I've had cats and they tend to scratch unless they are being otherwise immobilized). Jacob will get a nice owie that will involve broken skin and the nice sting of Bactine.  Lesson learned. And you can totally pull that "what did I say when you were playing with the cat?" This brings it all back so that Jacob understands that sometimes dad does actually know what the hell he's talking about.

If you have a larger animal that actually would eat Jacob in the wild given the chance, or if you really don't want to subject your son to bodily injury of any sort (but are ok with long lasting mental trauma), I offer Plan B:  great acting. I actually resorted to great acting often in my younger days when babysitting the neighborhood kids, around electric sockets mostly. Feigning temporary death is an underrated behavior modification tool. I'd say something like "you know what happens when you touch electric sockets right? You die." And I'd pretend to stand touch one by accident while pointing at it. I'd follow that up with convulsing and making spit foam, and then dying. The kids would be totally freaked out. I'd then wake up a minute later and shake my head like "what the hell just happened?" And then I'd feed them dinner, twitching every so often. They would never again go near an outlet. This technique is very applicable to your cat situation. Bother the cat while Jacob is watching. Get him to swipe and just go down in pain. Go balls out, roll around, scream, writhe and cry in agony. Jacob will make the association. Trust me. It works. This method also works with hot stoves, fan blades, knives and touching your computer. I don't always do what's right, but I do what works.