Hey,
Tell us a little about the cage you are keeping them in. What are you feeding them. How often are you cleaning the tank?
Take them to a reptile vet if you have one in you area.
Red leg is like a bacterial infection, it comes from unclean living quarters so I would seriously advise cleaning your tank from top to bottom. I use a bleach solution to clean my tanks, its 1 to 10 (1 part bleach, 10 parts water) and then rinse rinse rinse. They can also become suseptable to red leg from cage stress (as well as an unclean cage, it helps it along) so evaluate your tank size, I see you have 3 froggies, if they are getting big and have a small tank this will stress them out. If you just throw your crickets in there and don't feed them in a seperate container (I use a md plastic critter keeper) the crickets can chew on the froggies and stress them out too.
E-mail me if you need moe help.