Help: Is My New Little Baby Alright?

Hello,

Today I went to a breeder to buy a new friend (Nori) for my older budgie Iwo. 
At home, I saw that Nori‘s vent is bald (see attached photo) and now I am worried about him. ?

He and Iwo are separated, because I fear that Nori could be ill. What do you think? Are bald areas normal for baby budgies? Sadly I cannot visit a vet until Monday... And I really don’t know what to do now. ?

Nori and I would be very happy to get some answers.

Greetings, Lu