That's exactly what my daughter told me.
You need to do this ASAP if you are going to have them around your Grandkids
Are you talking about worms or heart worms or both? I can get hubby to pick up the kind that goes in their food.
both...
you should get “vet strength” wormer for parasites that treats all the parasites (hookworm, tapeworm, etc) and then put them on a monthly heartworm preventive that you get from the vet. (heartworms come from mosquitoes)
google ... canine worming
You will have to do it at least twice over 10 days or so (or the vet will do it for you) It is best to use Vet strength wormer that handles ALL the parasite types. You may be able to get it over the counter from a farm/feed store.
Just keep the kids away from any poop they leave behind and clean up all the poop in your yard until you know they are 100% worm free. Otherwise they will continue to get worms over and over again as they can pick them up from fresh poo that is left in the yard, the kids can pick them up also from dog licks (dog licks butt and passes parasite eggs on to kids). Your grandkids should wash their hands and face (puppy kisses) after handling the cute pups until you know they are parasite free.
My guess is that they have worms (95% sure) and this would be at top of my list of things to do until you find out if they belong to someone else who may want them back. Wait a week before you get them shots as I would hate to see you spend all that money on shots only to have someone come in and claim them.