Same breed different eggs?

[colby bush]

I have what I think are 3RIR hens 4 red sex linked hens and 2 production red hens all about 6 months old with a blue cooper Maran rooster at about 5 months old and the last 5 or 6 times I go to collect the eggs I've noticed out of the 5 eggs I get a day one of the eggs color is a little lighter and the egg is a lot smaller than the rest. Is this one of the hens just starting to lay her eggs or is it a different breed I have?

 

[oldhenlikesdogs]

It does sound like a first egg, though I think all those breeds lay a light brown egg, perhaps one is laying a really light brown.