SpoilerThe big brother is an omega, the test was wrong he is not an alpha.
* I knew it :3
*you can tell when he blush in front of his man ⁄(⁄ ⁄·⁄ω⁄·⁄ ⁄)⁄
I can tell from how perky his nip and booty. (≧∀≦)
Yeah that booty litterally shows that he was assigned bottom at birth.
Spoiler
The big brother is an omega, the test was wrong he is not an alpha.