We have several little graves of old pets outside of our house. Our neighbors have dogs and one of them has decided to dig up one of the graves of one of the cats to play with it. We have repeatedly put the cat back in and even moved the grave but the dog always finds that one grave and digs it up. Why does the dog do that to just the one grave even though there are older and newer graves in the yard?

The grave must not be very deep. It should be at least three feet deep. Then wrap the cat's body in paper or cloth (a throw or small blanket) and put a flagstone slab on top of the hole once it has been filled in.

Actually, hate to disagree with WG, but since we're getting ready to put our dog down and were thinking of burying him in our yard, we actually asked the vet how deep the grave should be. It should be no less then 7 feet. In our area it's actually illegal to bury an animal in the yard unless it's 7 feet or more.

Any less then that and you risk contaminating the ground, and you risk other animals digging up the graves, as you have found out.

Obviously you haven't buried the animals at a depth of 7 feet because no dog would be willing to dig that deep.

How is this dog getting into your yard? Have you spoken to the owners?

Actually, hate to disagree with WG
That's okay. I was going to say six feet (like people), but we've never had trouble with three feet. (We have a huge fenced yard and bury pets in a far back corner.) I defer to your expertise.

Our vets around here say it's illegal in Illinois to bury pets in your backyard (pollution of ground water), so of course they want to cremate the pet for $200+. My favorite vet recently told me, "Well, if you leave the clinic with your euthanized pet, we won't stop you."

Here it depends on the vet. Some vets say you need a permit, others are okay with letting you take your euthanized pet, as long as you assure them that you're following the restrictions (burying 7 feet deep, covering with a tarp).

The fact is, I wish anyone luck digging 7 feet in their yard. We got to 4 feet, hit clay, and that was the end of that unless we got a backhoe in. We prefer cremation, but the cost is outrageous, especially if you want the ashes back.

Have you talked to your neighbors about their dog coming into your yard?

Is the dog jumping the fence or do you not have fences?

The flagstone slab is a great idea.
I know a few people who have done tributes to their pets by cementing over the grave and placing a plaque there.