Kim is very excited about this development as there’s two different kinds of eggs in the nest. I’m sure she’ll chime in and explain why this is a thing.
Baby bird egg nest in the spring wreath that Kate hung on our front door.
My View of Life on the Dock
Good Morning Gloucester 
The blue eggs are most probably House Finch, they tend to nest in similar locations. The large egg is a Brown-headed Cowbird. Which is a brood parasite. Meaning they lay there eggs in other birds nests (usually smaller species) When hatched their chick is larger and due to size get most of the food from the parents and out competes the parent birds chicks. If I recall they may also push the other young out of the nest. There are other brood parasite species around the world but I think this is the only one in North America.
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To add to Rob’s’ comment–I think they are House Finch/Brown-headed Cowbird eggs as well however the House Finch is a most unsuitable host. Brown-headed Cowbird young do not survive in a House Finch nest because House Finch feed their nestlings mostly seeds and grains; Cowbird nestlings need a different diet, one that is higher in protein to grow and develop properly.
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Thanks for the lovely photo. The cowbird egg (thank you Robert Paterson) is a worry.
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Why, will they not fry up as good?
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Hope you like using your other door 😉
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