On the lake I live on this last spring I first saw a swan family 2 adults and 3 cygnets. Within a month the family went to 1 adult and 2 cygnets they have been faithful visitors daily. Just saw all 3 this morning and this evening only the cygnets came back. Is it likely after about 6 months today was the day the parent left them and if so were there signs of it happening. I did notice they did act differently. The adult started not being so generous with the food and also would peck at the cygnets lately. And does it always happen that they separate? We don't have many swans on our lake