Intruder!

Notice anything different? Well, the mother bird that laid the 4 light blue eggs apparently hasn't noticed the slightly larger one that's white with brown spots. This is from a hanging plant on my parents front porch (Laurinburg, NC). I think the nest belongs to some type of common house sparrows (one of them has a reddish head and throat), but I have no idea who the intruder egg belongs too. I've seen this on the TV nature shows before, but this is the first time I've seen it in person.

Attached Image:

You might want to do some research as to whether the next might be that of a "house finch," an extremly common, somewhat sparrow-like bird, whose male has prominent reddish or orangish upper body coloration.

As for the possible "intruder" look up "cowbird," as there are one or more such species which by habit leave their eggs with avian "adoption agencies."

Oh hoh... Of course, it is only circumstantial evidence that a Cowbird was there.