question about some neck feathers missing

[wac]

I have 26 buff Orpington pullets(?) five weeks old.Tthey all seem to be doing very well but 2 have a few neck feathers missing on one side of their neck is this a problem to be concern about or just being piked on a little. Thanks

 

[gritsar]

Just one side? Sounds like maybe a little pecking was going on OR they are just feathering in kinda strangely.