This video really shows how foxes can recognize a sickly pup and reject it. This is a sad but a true instinctual trait that most wildlife have (and many domestic animals). Some runts aren't suppose to make it, they are supposed to be rejected because the mother fox can tell they will not make it in the wild. In their own way they are trying to prevent the suffering. At the time we didn't know this was the case with Mini...she could have been just 'small' but that wasn't the case and the foxes knew it!

And I can't believe I didn't recognize this before...I had never seen my foxes all react quite like this...by shacking their heads and walking away.
At the time of this video Mini hadn't gone to the vet yet. I hadn't yet discovered Mini's two front legs were completely deformed and practically unusable at birth. It wasn't until she was old enough to start to try to walk that we noticed this.

It is sad. But also very interesting and helpful to know this is how the foxes react to sickly pup.
Regardless it's never a waste of my time to try to save them, no matter the foxes opinion on it.

Some foxes that couldn't have a good quality of life or survive in the wild, can still thrive in captivity. Their is a lot more assistance provided to captive foxes with conditions that of course, wouldn't be available to a wild fox.
Even though our foxes are captive foxes, they still rely on their wild instincts!