Questions about kitten tails

Hello,

I currently have two kittens, roughly 4 weeks and 12 weeks. The elder's mother weened him several weeks ago, but the younger one's mother has decided to nurse him. Here lies the issue... the younger kitten's tail tip fell off at approximately 2 weeks old. Internet research says it might be something called Neonatal Isoerythrolysis. The elder kitten's tail now looks kind of bent about half an inch from the tip. I'm wondering if the elder kitten isn't getting Neonatal Isoerythrolysis as well. If so, should I stop them from nursing? If so, how? Should I just keep the mother separated from them and ween the younger one? The older one is on solid food.

From what I can find, that disease would be causing far worse symptoms and has nothing to do with tails. Plus the antibodies come out in the colostrum not regular milk so there would be no point in weaning them now. I suspect some kind of injury occurred, maybe that mama cat bites their tails or something.

Yeah I agree as I don't see this as something caused by nursing from that mom.

A kitten who had the tip of their tail come off at 2 weeks was born with something up, but now this other older kitten, had a perfectly shaped tail before and now does not?

That's really odd. 

I would say either this is a very strange coincidence or mom is chewing on the tail tip, which would be highly unusual.

I would definitely be keeping a very watchful eye on this, checking for wetness or signs of it being chewed on too.

A 3 month old really doesn't need to be nursing anyway, it's pretty hard on mom, full teeth and claws hurt.

You can always feel any deformities in a tail by running the entire length through your fingers, sometimes you will find like a knot then a kink or turn.

It's caused by inbreeding, mom/son, sibs, etc.