Those pictures you posted help a lot. This is what I think, gene by gene, of your dad mouse:
Your dad mouse is A
/a or A(vy)/a. The A
or A(vy) produce the fawn/yellow look, even though your dad mouse is NOT yellow in appearance. the little "a" means he can father black, blue, light gray colored offspring.
In addition I would say it is very likely he is also b/b which is the brown dilution and which can render black eyes into a ruby brown type color. Doesn't always, but it can. This would also account for the brown tint you noted.
I would venture that he is probably c(ch)/c(ch) or c(ch)/c the c(ch) is like a "hypo" gene in snakes, it dilutes the dark colors and renders the yellow into white. This would result in a mouse with no yellow on the individual hairs.
That dark gray one is a "Blue" mouse, which means papa is either D/d or d/d ... I'd venture to say, since he appears to be a lilac mouse, that he is actually d/d... in other words, if it wasn't for his fawn gene at the A-locus, he would be a true lilac mouse. So in essence he is a lilac fawn.
if ALL of his offspring when crossed to a pink-eyed non-albino female are pink eyed, then he is also p/p (pink eyed)... if roughly half are pink-eyed when crossed to a non-albino pink-eyed mouse, then he is P/p... since not all his babies are pink eyed, I'm guessing that he is P/p and the recessive pink eyed gene could be slightly affecting his eye color also.
And since I'm at it... since he had broken marked babies, he's also S/s which means he's het for piebald.
The little gray broken marked there, if it has pink eyes, I would suggest that is a true "Dove" mouse, which is the same as a pink-eyed black mouse.
The lack of white or light colored tummies rules out the mouse being 129P though it was a good call and might have been that mouse if we didn't know all the additional information about the babies.
I did just have a sudden thought, however.... There is one tiny little chance that I'm completely wrong about the fawn.... if the papa mouse is JUST a lilac and not a fawn, there IS one other way of getting yellow babies when crossing him to a yellow mouse, and that is if they both carry the recessive "e" gene which in its homozygous form results in a non-obese (but VERY beautiful) yellow mouse....
The way to test this final theory? If you have two of his black offspring, (or black broken marked) of opposite genders, breed them together. If you get yellow babies, it's recessive yellow. (why didn't I think of this before?)
In any case, I don't really think it's recessive yellow, as those have very clear yellow babies, none of this dark umbrous look like some of your babies have)
I just have woken up really sharp this morning!
