I have a light sussex hen (1 year and 3 months old) who used to lay light brown eggs. Recently, I found her eggs are lighter and lighter in color. Today I picked one up from her that is almost cream colored. Is this a natural thing that do happens or does it mean there is some trouble with her, like mal-nutrition, disease. She looks okay to me, and she's still laying a lot, almost everyday, and the shape of the eggs are not changed.