Silkie beating up other chicks?

[stina3246]

I have 3 chicks. 2 chicks are 3 weeks old and 1 is 2 weeks old. Both 3 week olds ( a silkie and a cochin) are Bantams from the same batch (or at least from the same breeder) The Silkie is WAY bigger now then the Cochin but were the same size when I got them. The RIR is 2 weeks old but the same size as the cochin. My Silkie has taken to leaping up in the air and "kicking" the other 2 chicks. It doesn't seem to hurt them but it annoys them. Is this normal?

 

[stina3246]

no ideas?

 

[Elite Silkies]

He/she is just showing the others who is boss.