I agree with thatbags about Facebook, emails and skype. We have basically the same family set up with one of our daughters, as regards them coming many miles, and staying for a few days.
We Facebook and email and phone and skype.
But what we also do, is make sure that we are up when she is[she rises earlier than her husband], so we fit in the more personal stuff then.
That way, we and her have said what we all want to say, and the rest of the time is whatever it turns out to be.
Even her shower time can be used for quick parent to son chats if you are desperate.