One of my puppies died?

i keep my 3 month old puppies in a large outdoor run for their safety. one day they were out and had gotten under the trailer and were tearing up some insulation (fibergl) that we had stored under there. (how they got out is that they finally got big enough to climb over the gate). a couple days later i was drawn to the run by crying. one of 2 pups was in terrible pain and one was looking miserable. i took those two out and brought them in to warm and comfort them. the one crying quit. they both slept. i thought they had a gut ache from gulping ice cold water too fast. once they seemed to be better i put them back in the run and they ate. the next day the pup that wasnt crying was dead. the other seems to be ok. does anyone know what to do if a dog ingests fibergl insulation as i suspect this to be what happened. (the dead pup had bloody mush draining out his back end) if this happens again (i pray it dont) i would like to be prepared. thank you. no flaming plz.