Appears to be some confusion here as the burd in question is the bird posted in the 1st post by the OP. The other birds posted are from another member showing an example of their Brown Leghorns.
To the OP, your bird is looking built more like a well summer at this point. While ear lobe color is the differentiating point, it does not develop for a few more weeks. That is the point at which it will become the telling sign