They always begin whistling only when they're on their own. I bet they start doing it all the time pretty soon.Me too.
My fiance has heard one of them do it too. They seem to only do it when we are out of sight.. lol I thought I heard them do it while I was sitting here but it was one whistle from each, like they were finishing each others sentences.
You would be correct thats what the come here whistle is
Aly here is a link to what the come here whistle sounds like just click play and it gives you a little clip of itMaybe Which is the come here? lol