I live in Michigan, USA and in the lake by my house there are 2 couples of mute swans.

One couple has 3 cygnets, 3/4 of the size of parents by this time, all very healthy. The other couple has 2 cygnets, and they were born much later. I am worry because they are very little. Today, I saw them and one grew substantially, while the other is still very, very little.

Comparing the triplets and the twins, the survival during winter looks very poor for the little ones. What do you think? Do the twins have any chance?