When I was around twenty my Mom used to call me every other day or so just to have a chat. One day, after she asked me how my day was, I shot back something along the lines of: "I don't have anything to tell you, really. You're calling so often that nothing new manages to happen in between the calls." So, she stopped calling. I would go home every other week as usual and everything seemed fine. It was only much later…
When I moved away from home I kinda thought it would be the same with me. After all, not that much happens during the average working week. I worked, I ate with friends. So why call all the time?
Turns out I think they just missed me. To a degree parents live through their kids. Are you enjoying your work? Have you found a girlfriend? It's like living through that age again.
Technology really helped. The last few years before they died they'd call weekly to check on their grandchildren. Often short calls, but still pretty good. In fact my last contact with my mom was via a video chat.