Colby is off of bottles already, but now the struggle is what cup will he use?? We went through this same battle with Blake. The will drink water out of any cup you hand them... but put milk in the same cup and NOOOOOOPPPPE!
There is ONE style cup that Colby will drink milk out of... same kind as Blake. This cup is hard to find and is usally about $7 a cup. At least, we had 3 left from Blake.
I'll keep trying to convince Colby that he can drink milk out of other cups. I think Blake was about 18 months when we finally convinced him.