Help sexing 6-7 week old chicks

[ChibiChicken]

Just found out that two of my four chicks are cockerals, so they're going back to the breeder, and now I'm paranoid about my other two
I have a buff cochin and a light sussex here, very suss about the Cochin. She/he is quite skittish, and is always the first to chirp at danger and alert the others, even before my two confirmed cockerals. Light Sussex is around 7-8 weeks old, Cochin is about 6 weeks. Here's some pics, what do you guys think?





Light Sussex: thinking pullet?

Buff Cochin: I'm thinking cockeral

And yes, the Brahma and Pekin in the background are boys lol

 

[ramirezframing]

looks like pullets so far

 

[mshuntjump]

pullets. A little iffy on the cochin, but I'd say pullet so far.

 

[Frizzle13]

Both look like pullets

 

[ChibiChicken]

Oh thanks guys, that actually makes me feel better

 

[ChibiChicken]

Sussex was a pullet, Cochin a cockeral, just as I thought. I ended up with 3 cockerals and 1 pullet from my 4 chicks lol...