What these "Ticked" babies from otter and self parents?

[Floofbunny]

So my aunt has bred her black otter to a Black self dutch. In the litter their is the usual black, blue and black otter.
But then theirs these two mystery buns.

My first thought was agouti. But that's impossible as the parents are black otter and black self.

So I thought of sable, tort or even steel.
But they look ticked. Steel doesn't show on otter does it?
Looking at these "gold tipped" babies what could they possibly be?

Mum is black otter Lionhead cross, dad is black dutch. Babies below

 

[Lord Trellis]

Do you have any photos?

Its not uncommon for this to happen. Sometimes the parent bunnies have hidden genes in them which are not obvious due to blood lines and years of breeding. If a gene is still strong from another breed, then one or two of the babies will be different to the parents.