Their take on the situation.

My understanding is that they were told that their mother was dead.
They never received any gifts or cards form my (their) mother.

We stayed in touch, a couple of visits from them to us, some from us to them, but the contact was, and still is primarily birthday and seasonal cards.

Bert has sadly since died.
I am in contact with some of his children on line. In fact, 2 have left comments on another of my blogs.

We are still in contact with Ken, the occasional phone call, cards and on line. I have been in contact with one of his children on line.
We both know where each other is, and contact is made on a casual basis. That is not to say that we don't care.

Tomorrow, contact with my Dad's son.