Snickers' color genetics are:  bb + EE

 

Sarge's color genetics are:  bb + Ee

 

Both parents can only contribute a 'b', so all offspring will be 'bb' - chocolate.  No black which requires at least one 'B'.

 

But will there be yellow?  Snickers has EE, so she can never contribute the recessive 'e' to match the one from Sarge.  Therefore, all offspring will either be EE or Ee.  No yellow, which requires an 'ee' combination.

 

Possible color combinations for Snicker/Sarge offspring:

 

bb + Ee = chocolate (able to tproduce yellow offspring.)

bb + EE = chocolate (not able to produce yellow offspring.)