Maybe a dumb question but im new to breeding....

[The Serpent Merchant]

This is the outcome if your yellowbelly is het pied

Genetic Wizard 3.0 calculations by


And this is the outcome if your yellowbelly isn't het pied (50-50 chances of your yellowbelly being het pied or not)

Genetic Wizard 3.0 calculations by


There will be no visual difference between anything that is het pied or not so from this pairing you have no way of knowing if your yellowbelly is het pied. I would try to breed the yellowbelly to a 100% het pied or a visual (homozygous) pied to find out if your yellowbelly is het pied or not.