You are welcome!
I am sorry for you.
Had to be really hard...
To me, your hen
is Silver/Splash coloured.
But more pictures would be indeed appreciated!
Ooooooh... that's so interesting...!!
Pictures would be great, yes! Especially since the ones showing Lilac/Lavender Indian Runners are so hard to find...!!
Okay... so
none of them are actually (solid) White...
Good to at least know that.
Yes.
The brother clearly has the Runner gene : you can see the pattern on his body looks like the Fawn and White one.
(Very easy to guess especiallyt thanks to the
so perfect pattern on his wings...)
He also has the bib gene : again, you can easily guess it by looking at him, given he has so much white on his front...
...Your white drake looks like his brother, but just
whiter...
So : he has the Runner AND the Bib genes, but has inherited of a more diluted phase
(or whatever you would call that)...
(NOTE : even though I have learned a lot about colour genetics, I am still just guessing here!)
That would be possible, yes.
Fawn and White duck
do carry the Brown gene...
right?
And
if he carry the Runner gene - meaning the
Pied gene -, then your boy should
also carry the Brown gene...(?)
Now we know a bit more, you are probably right : not only they are partly Runner patterned, but one of these ones is also Brown coloured...
Are you refering to a
Calico spot?
An example would be the Blue drake here : https://www.duskyfeatherswaterfowl.com/pencilled-bibbed-black
If your Blue drake has an
ordinary bib - meaning the smaller ones kind -, then I don't think he would be the father of your brown ducklings... especially given one of them probably carry the Runner/Pied gene, and your Blue drake does not...
(I think so at least...?!)
I would then think your Lilac duckling to be the offspring of your White drake, and your Silver/Splash hen.
(I even have looked at THE CALCULATOR to be sure it could be a possibility!!
I put "Chocolate" for the drake, and "Silver/Splash" for the hen...)
Do you have a picture?
My Silver coloured Duclair looked like a Snowy duckling...
I was then so confused, since I did not buy eggs from a Snowy coloured duck...!! (Nor from a
Splash one, in fact...!!)
(I took my
sweet time to understand this duckling was a Splash coloured Duclair drakelet...!)
That's a shame.
I am really grateful to you for posting a picture of your Splash Indian Runner drake : even though this colour is just splendid, pictures are really hard to find...