soft shelled are not common but can happen in the real young or ill birdsI should mention, all 3 eggs she laid today are all fully formed hard shells (since most of the other posts I've read about this seem to involve some of them being soft shelled).. However, she didnt lay any yesterday and she typically lays one every day.
it is rare to have a bird lay even two a day maybe she had late at night
and you have another layer?