Hi, If they become lethargic or you notice blood in the stool or vomit, they needs to see the vet promptly. As this is a sign of serious illness including a parasite infection or a blockage among other things. This sounds like a case of upset stomach, since all of them have the loose stools I suspect it is something they ate or a bad batch of food. You can self treat this at home unless any of the above symptoms start presenting.I would recommend skipping the next meal and allow their stomach time to rest first. Often the GI track is in such a uproar that anything put in it will come cause more upset. Make sure it is a couple of hours before the next meal. I would then start them on a bland diet of boiled chicken and rice to help settle the stomach.(1 part skinless chicken Breast to 3 parts white rice)
I am concerned with them becoming dehydrated as this is quite serious with dogs. I recommend giving them unflavored pedilayte to replace the electrolytes.
You can give Immodium or Kaopectate Here is a link with dosage instructions: http://www.peteducation.com/article.cfm?c=0+1459&aid=1432
I would suggest monitoring them closely over the next 24-48 hours. If they are not doing better in 48 hours or they have any of the following symptoms they will need to see the vet.
Walter
Breeder
Breeder and pet health consultant. Have spent a number of years with dog rescue, training and health