HELP! One of my 3 day old chicks can't poop!

[JiJis hens]

I love pics. I love learning about new breeds. So far I know three breeds

 

[stellacorina]

Did you check for pasty butt that may be the problem :/

 

[gg706]

 

[gg706]

Chick 1 looks rumpless first 2 pics
Chick 2 definetly an Araucana rumpless and has tuft 2 pics

 

[gg706]

 

[gg706]

Chick three araucana has a brown face and rumpless 1 pic... it wouldn't hold still to get a pic!

chick 4 araucana rumpless and tuft 2 pics

 

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[gg706]

Chick 4 Blue Laced Red Wyandotte 1 pic
Chick 5 Blue Laced Red Wyandotte 1 pic
Chick 6 araucana rumpless no tufts lavender with yellow head?? 2 pics

 

[gg706]

 

[gg706]

chick 7 lavender orpington
I have several BLR Wyandottes in various color variations and 3 lavender orpingtons.... the orpingtons basically all look the same
i think chick number 2 is my favorite the black with the yellow splashed face