Answer

Hi...

I asked if they're using the same area of your lawn because that would make the behavior easier to control. For now, I'll assume that they are. Although there are a lot of things you can do that will keep some cats away from places where you don't want them to be, the most effective deterrents are the electronic ones like the ScareCrow or CatStop. Some pet supply stores sell them, or you can buy them online.

You can also try giving the cats a "litter box." I'd use a large plastic storage box with very low sides -- the kind that's meant to slip under a bed. You want to make using the box as much like using the lawn as possible. Put very little litter in the box -- just an inch or two -- and put some of the grass or soil they've used on top. I'd suggest using Cat Attract litter. You can buy it at most pet supply stores. Put the box in their favorite spot. When they're using it consistently, you can move it, literally inch by inch, to a location that's acceptable to all of you.

Some other things you can try are keeping the ground moist -- cats prefer dry soil; putting bramble or rose bush cuttings on the ground in their favorite locations -- this will be uncomfortable underfoot; or scattering orange or lemon peels around their favorite areas.

If the cats don't need to roam and stay pretty much in your yard, I suppose you could fence part of the yard and let that be their own place to do as they choose. The Purrfect Fence is relatively inexpensive and easy to install.

This is going to be a tough habit to break because the cats are just doing what comes naturally. They don't understand (or care) that kids want to play and humans want to walk in the area they consider a perfect litter box.

I hope this gives you some ideas. If you'd like to talk more, please feel free to write back to me.

Missy