Sometimes I think H doesn't realize how important he is to us.
Hey Maybell, the above really caught my eye because at times I feel the same way about my WAW. Our kids and the animals have always meant the world to her. I can only imagine the pain/confusion, etc that she must be going through right now to not be with them 24/7. So although your H's actions (or lack of) may say one thing, you have to imagine the internal struggle he must feel inside.
I would advise against the text because to me it comes across as pressure or controlling. My W will pick our 3 kids up a day or two midweek, then at some point during the weekend. From day 1, I've told them that if they want to call either of us, they can. If they don't want to stay with W at her friend's or with me at the house, they don't have to. I would encourage your kids to give H a call if they want to speak with him. Let H feel what he's missing out on as opposed to you forcing it upon him.