what breed this 4 chicks

[Aziza]

Hello everybody, I received some eggs from a friend, they where posted and then flew in to us in Nouakchott. From 21 mixed eggs medium/ big size only hatched 5. Have no idea what they are, I have numbered the photos and Nº2 I guess it might be a Brahma or a Cochin. Number three was a round big blue egg and he/she was born with the neck skin balloned with air inside, it looks better today, I guess it might be a Cream Legbar but never saw in your photos this coloring and one line only from head to end of back.
If you could help me identifying I would be very happy. I opnly have Bantam's and I believe those chicks might be medium or big size.
Two of the photos with the mother that took care of them.

 

[oldhenlikesdogs]

Looks like a black cochin, and a naked neck. Not sure on the two lighter ones.

 

[Aziza]

Looks like a black cochin, and a naked neck. Not sure on the two lighter ones.

Thank you, you confirmed my thoughts for the dark ones. I don't think is a naked neck , the chick had her skin around the neck swollen like a balloon of air at birth now the air has gone and I hope feathers will grow. It was born from a blue pastel egg