A Cream Legbar crossed with a Rhode Island Red will not produce a black and white chick. Either you are mistaken about which birds were the parents or you are mistaken about the parents' breeds.
The cream gene of Cream Legbars is a recessive dilute gene that only affects gold base coloring. They are genetically the same color as Brown Leghorns, but with the cream gene diluting the gold/red coloring and the barring gene, which applies 'bars' of white across a bird.
Since the cream gene is recessive, cross bred chicks carry the dilute gene, but it doesn't express.
Is the Easter Egger silver?