I was sad to hear the story of the Bliss family losing their beloved pets, and I know how they feel. I now know what killed my pets a few months ago, suddenly out of nowhere. I too let them out in the yard and on two different occasions had one of my dogs fall victim to some mysterious ailment that killed them within 20 to 30 mins from the time they went out to the time i found them. the first died before I even knew there was a problem and then about a month later the next one died, but I found her laying in the yard not able to get up, salivating and limp, shallow breathing, I was in a panic, wrapped her in a blanket and we rushed her to the Vet. but she passed away just before we reached the office. Wanted to do a necropsy but just didn't have the funds to do so, so never knew what the cause was. Was so perinoid after that, we just stop letting out pets to play in the yard, kept them on the deck instead. Now thank goodness I know what happened and it is a relief. Went out to pick some of the mushrooms and sure enough they are poisonous! Thought about it back then but dismissed it, wish I had done research on them then. Sorry for your loss Bliss family, but thankful for your making us all aware of the dangers lurking in our own yards. Thankyou, Sincerely Terry H.