I noticed that some of the others we have replied to my post mentioned something about red in the feathering.
Roosters are more prone to having red on some parts of their plumage, hens are more prone to having it other places--so red in the shoulders/wings is more likely in a rooster, while a red/pink breast is more likely in a hen (black breast being more likely in a rooster). Of course, this is only useful for some chickens, because there are many breeds that are all one solid color, and others where the roosters and hens are bred to be the same color. (Rhode Island Red hen will clearly have plenty of red, while White Leghorn rooster will have no red on him, for example.)
Roosters often have brighter, shinier plumage than hens--but Easter Eggers can be such a mix that there's a lot of guessing involved.
Well two of the four 8 week olds have feathering that is all white and they have no hint of red or even pink in the peacomb. The third is kind of black and has some red in the peacomb, but not as red as the fourth.
The fourth (the chick I had the question about originally),. Has a much redder peacomb.
The reason I asked if you had photos of them all is that comparison (visually) is often easier than looking at one in isolation. Pullets do mature at different rates, so sometimes the redder comb is just an early bloomer. Every pullet you've got will eventually have a bigger, redder comb than the one you're currently concerned about--and each one is likely to get a redder comb somewhat suddenly, too. But it can be quite a guessing game, trying to figure out which ones are males and females as they're going through the process.
It does seem likely that you have a cockerel there, but it could take some more weeks to be sure.
About pictures: it looks like your camera is focusing on the chicken wire, rather than the birds. You might consider taking any future photos with the camera inside the pen, instead of through the wire. (That way the camera won't be showing us such clear details of the wire when we want to see the chickens!)