Means the bird carries the Melanizer gene, it's a gene that usually either encourages extra black patterning/pigment in the feathers or with silvers, it often encourages a lighter color as seen on these two birds. A normal silver hen would look like this -
Salmony breast, darker gray body, different neck black/white ratio.
I don't think she's carrying dilute/cream however she may be carrying Columbian. A LOT of Easter Eggers carry it, and it also washes out the salmon breast. In fact she'd probably require Columbian to look that way, most melanizer on duckwings actually darkens them into what is known as "Brassy Back."
So to clarify to the OP - You have what I believe are a bunch of birds who are either E/E with barring or E/e+ with barring. The recessive, hiding e+ (duckwing) especially in hens is what allows, in a mating of two birds carrying that one gene, you to have a 25% chance of a duckwing again. You might also get some Creles too if you do this more often. If both parents were barred, what likely happened is that since your male is incomplete barred, half of the offspring will be sex-linked, thus, 25% of the offspring will be a normal duckwing instead of a crele. So, you got yourself there a nice little girl that normally is a found one in every 16 possible birds.
ETA -
To answer on Columbian vs Silver. Silver and Columbian are two different genes. What you're talking about is how most "Columbian" colored birds are in fact carrying the silver gene. Columbian color is basically black hackles and tail (or saddle in males) on a solid bird. If the bird is carrying gold genes, it's often called a Buff or Buff Columbian. Otherwise it is sometimes referred to as a Light, a Silver, or a Columbian.
