Thank you so much for the information that is really helpful to know.It sounds as if both your birds also carry recessive white. Recessive white covers all colors with two copies, so it needs to be supplied from both parents. Also - any of the other normally colored children have a 50% chance of getting recessive white - so their children will have White come up too. If you don't want White - you will have to do a LOT of breeding - and test breedings - until you can eliminate the recessive white from your birds. Since you used a Lavender hen - they are also split to Lavender and carrying Partridge - so could throw Lavender OR White chicks or who knows what .. you are really getting into a genetic stewpot there.
richard