We have had a lot of Cardinals lately. Many of them are young birds. You can tell because they still have some fledgling feathers and they look like teenage Cardinals. The boy in the set looks nearly full-grown, but the Lady looks recently post nestling.
The lady Cardinals go through a lot more color changes than the boys. The boys turn red and stay red. But the girls are first a kind of light taupe or beige and develop color in their wings and face and tail as they mature. They are also a lot more variable in their coloring.