i have some mice (will do better pics later) and i thought they might be silver burmese from a post i remembered of some of sarahs (dawson) mice, but i've been looking on finn mouse and i see 'pearl' and then pics that are yours caits!! and it looks very similar, these are from a chinchilla buck x himi mating.
you cant tell much from this old pic as they are too little, their colour has really changed now,

you cant tell much from this old pic as they are too little, their colour has really changed now,