Are these mom raised? if not what are you feeding them and how much? If you can, get the C&D Antitoxin, and give it to all of the kids asap. This is short acting, but it last for a few weeks and doesn't need the second shot to take effect. Then you need to get baking soda into any that seem bloated, doesn't matter the amount just as much as you can, rub their rumen ( tummy on left side) If it is tight or you can feel the gas KEEP RUBBING WITH SOME FORCE. That will probably cause them to burp. That is a great sign!
If it's enterotoximia (sp?) the only thing that would them is a double dose of the Antitoxin. It's great stuff to have on hand just in case...