Damn! I was hoping, as you know, that your kids woudn't have to deal with this! That first time the world lets you know you're not white is the worst! That first time the equal, wonderful world you think exists is shattered, well, you know, it breaks something in us. It's a true questioning of identity.
That said, I'm so glad your daughter has you to guide her through this. It's a confusing and hurtful time. Been there, took me 40 years to get over it, and well, I'll never really be over it, right.