That one has different barring because it's male. Males get two copies of the barring gene, one from each parent. They basically have twice as much barring as females (which can only ever have one barring gene, from their father), which makes them look lighter.
I've got 70 in my flock, and 2 other roosters, so I'm going to need to segregate them. I've got BRs,golden sex-links, wlh, australorps, araucana, etc. I'd have no way of knowing whose eggs were whose and Big Daddy, my australorp rooster, likes everyone. Even my silkies!