Can you help with this wedding conundrum?

I am getting married in March. This is not the first marriage for either of us. We are planning a very small ceremony with only our children and (his) grandchildren in attendance. The only other attendees will be the four people we invited to serve as witnesses, fellow members of our faith. My family knows I am planning to marry and I am starting to get all kinds of questions about the date and time. I know at least one close family member thinks I am angry at him because I have not invited him. I am thinking about sending some kind announcement just to let everyone know when we are getting married and explaining that it is very small – but I don’t want to hurt anyone’s feelings because they aren’t invited and I definitely don’t want to be seen as sending the announcements as a way to ask for gifts. Any thoughts on a great way to let people know about our plans?

Just as an FYI, I am not particularly close to most of my family but we do all get along fairly well.