I don't follow your logic here. Are you saying that if something hasn't happened thus far - then it never can happen? There must have been a time in the case of the person who assaulted children in their beds in Portugal that he had never assaulted a 7 year old. But then he did.
There has to be a first time for everything.
No, absolutely not. Despite the saying that there's nothing new under the sun, I am not claiming that something can not happen just because it hasn't either before or since (to our combined knowledge anyway).
I do wonder why people think that it's a possibility. A few people have proposed it as an alternative to Andy Redwood basing his recent comments on the dog alerts.
At first it I thought I was just unaware of these other cases. I asked on other threads a couple of time, but got no reply so I went to Google. I couldn't find anything there either. It was quite difficult to know what to Google though, so again, I thought I might've been missing something.
To me it seems like one of the most unlikely scenarios. As far as I am aware, someone unknown to the victim has never entered the victims property, caused a death, then taken the body with them.
Bear in mind that in this case there was only a 50 (ish) minute window, broken up by a check at 9:30 which was about 20 minutes in to that window, during which everything was quiet and there was no signs of either a murder or a break in.
There are many reasons why one would conceal the body of a known victim. That happens all the time. There are also cases of children being removed from their homes alive by strangers then coming to harm, as has been mentioned further up the thread, though thankfully that is rare.
But why would someone remove the body of an unknown victim from their own property?