I'm colorblind too and he's not seeing the colors for the first time he's seeing the right colors for the first time I dont know what kind of colorblindness he has but the most common one affects the way you see green and red but there are other kinds. I've been through some situations like buying a white shirt and wearing it for months and then find out that the shirt was green and not white, failing to get a driver's license and i always have ask my sister or my mom if the filter i used in my pics look good cuz i know that the way i see it isnt the way it really looks...
