Okay, so we want to start this off by saying that dogs are somewhat like children in that they are a large responsibility and require attention and care, but that's about as close as the comparison gets. We know that dog parents like to refer to their dogs as their children, but it's acceptable up to a certain point. That point is when the health and comfort of others is impacted negatively, and for the original poster of this frustrating Reddit thread, that point had been reached and exceeded!
It all started when one woman was informed that her sister-in-law planned on bringing her dog along on their family vacation, despite this person (the OP) being highly allergic, as well as the vacation service not accommodating pets. Instead of thinking for a moment that perhaps it would be an idea to find suitable pet care options for her dog while the family enjoys a nice and comfortable vacation, her first instinct was to both make her sister in law uncomfortable (and sick!) as well as potentially put the family's vacation in jeopardy for not following the accommodation's standards. People really need to be less selfish, and more responsible with their doggos!