Thought this budgie was a girl!?

[SweetBlueberry]

Hello everyone, we have 3 budgies. We had a male (blue) and female (green) and then got a third which we also thought was female. When we added the white bird the blue male ditched the green female, and now the white bird and blue boy are often seen together eating and grooming each other, however the white birds cere which used to be pretty light blue and white around the nostrils, is slowly getting pretty deep blue. So, is the white one a female or a male?

Thanks!!

 

[Owlet]

White one is definitely male.

 

[Jcas]

Yep, both blue budgies in the pictures are males. Green one is female.