Need help finding out the sex of these chickens

[Paty]

Someone gifted us four chickens two are Australorps and the other two are Rhode Island reds. They said they were all hens not sure how old maybe four months when we first got them. We believe some are starting to look like roosters. Please help us identify the sex?? Also husband said the feathers on the neck flair up when they try to fight each other.

 

[sourland]

The RIR in the third picture is a pullet. The other 3 are cockerels.

 

[HorseGirlAbby]

All cockerels except for the red one in the third photo. You will likely want to separate the pullet so the cockerels don’t fight over her.

 

[GlicksChicks]

All cockerels except for the red one in the third photo. You will likely want to separate the pullet so the cockerels don’t fight over her.

x2 that the red one in the third photo is a pullet.