I have 7 nametagged trusting foxes in a fully enclosed area with shelter and berries for them, but every once in a while 1-2 of them will disappear from the realm all together and I have to breed another one. I can't see how they could be dying off so I assume this is a bug. I've seen this issue brought forward previously but in my experience, it has still not been resolved in Bedrock 1.16