Me too, I'm aghast. That he has kept them from us for almost 3 weeks when they just lost their mother when we have been the "other" set of parents to all of them, almost, is just killing us. They have no idea why we are not around when their mom is gone. We've always been around. They are just little kids - 9-6-3 years old with no way to understand and we can't even talk to them.
It's so hard to stay on a level plane right now and wait, it really is. They want to ask us where there mom is, if they are going to be okay, and all the things that they need to know right now
We have no intention of trying to remove them from him, or to say bad things about him to them. She's dead - that should be enough.