Do I have a rooster among my pullets?

[firsttimechickenmamainRI]

I purchased 12 pullets from Tractor Supply and I have long suspected one of my Barred Rocks to be a rooster. "He" has been more aggressive and bold from the start and the crest and waddle have developed more than "his" sister. I've heard males are also more white than females. I am brand new to this but want to know if I need to find a new home for him as I was not planning (nor do I have the needed permit) to have any roosters.

Thanks for your thoughts! I've posted first pictures of the suspect and then of his sister for comparison.

 

[firsttimechickenmamainRI]

By the way, they are about 6 weeks old.

 

[sourland]

Your suspicions are correct.