Dilute green baby?

[HoangQuan]

Here's the chicks from the latest clutch of my gouldians. I thought all of them would be normal green chicks with purple or white breast since both the parents split for white breast.
But this morning I checked the nest and saw this 4 chicks almost fully feathered. 3 normals but the other one is very strange .
A dilute green?
I don't know, I saw lots of dilute green chicks, but never see any dilute with this light, almost yellow-grey colour. But this is obviously not a yellow since the beak is black. The parents are both BH GB, the grandparents are the same. so how can this happen?
I also have a double factor yellow cock in the cage, so I wonder if the chicks are from him. but even when that happen, all the chick must be dilute(male) or yellow(female), why I have normal chicks here?
Any ideas, guys?

[bugaboo5]

I don't think the pictures are showing? Congratulations on the chicks.

[HoangQuan]

I don't think the pictures are showing? Congratulations on the chicks.

Yeah I don't know what happened, the link didn't work so I have to edit the post and add the attachments. Now you can see it!!

[bugaboo5]

Hi - thanks for fixing the photos! Oh yes, the baby is definitely not green back. How this is possible may remain a mystery. It probably means that maybe your green back parents have the yellow gene somewhere down their history - maybe great grandparents or further back. You get dilutes (which can only be male) by having a parent that is carrying a yellow back gene. I would wait a bit and have the Gouldian experts chime in on the exact mutation of your beautiful baby. It appears a little lighter than what I'm used to seeing in dilute babies. Please keep us updated on the baby as it feathers out. Congratulations either way.

[HoangQuan]

I think this is definitely a dilute, but how it got here is hard to understand. You know, I know my green back gouldies, they are obviously not carrying any yellow genes. Yellow gene is hard to hide especially with the purple breast. All of my birds are purple breast or purple breast/ white breast. so if one of them carries a yellow gene, it will show off as dilute(if the bird is male- Zz) or yellow(if the bird is female-zW).

[nixity]

Paired to a normal hen a DF male will only throw dilute males, but since you said the mother is /White - if the DF is white breasted or split for white as well, you could get visually yellow WB SF Yellow males.

Not all eggs have to necessarily have been fertilized by him.
This is the risk you take when colony breeding, but it's possible he fertilized one of her eggs and that's where this baby came from.

It's the only possibility.