Cockerel or pullet?

[brantchickens]

My 3 barred Plymouth rocks are now 13 weeks old, I bought them when they were 9 weeks old and the breeder I bought from assured me that I had all pullets. I'm starting to question the one now though because the barring looks more like a cockerel and the past week I've noticed the comb and wattles have grown more than my other 2. Just looking for some opinions

 

[brantchickens]

Here's a picture of one of the other pullets

 

[oldhenlikesdogs]

That's a rooster in the first picture.