Can real-world color genetics predict a foal?
Separate the observations
A coat description, body white pattern and face marking are different fields. Save all three for each parent and foal so that an apparent color change is not confused with a changed marking.
Patterns in official materials
Developer materials discuss Tobiano and leopard/Appaloosa patterns and face markings. Pattern variation is procedural; these descriptions are not a complete finite coat catalog.
Compare actual outcomes
Use the breeding notebook to search related pairings and compare observations. No Punnett-square probabilities or real-world allele notation are applied.