that I see more often misidentified than this one, and I had my issues in the beginning too. All of these are the same species a Brownheaded Cowbird. The first two are youngsters. A juvenile that is morphing into adult feathers, a stage that I love, it looks so cool because they all have different markings. The one next to it is a baby, and I was a little surprised to see that yesterday, so late in the season. The pink edges of the beak, the speckled brown feathers and the cute appearance are tells. The other two are adults - a female and a male. They get a bad reputation but are fascinating native birds and do not act out of malice. If you are interested to learn more about them, Audubon has a great article about them here.