User blog comment:TheAnimatorCartoonistDude/My First Fan Theory- Lincoln's Adopted/@comment-30102612-20161008002303/@comment-26901681-20161008005121

I knew somebody back in high school whose hair started to turn gray at age 13. It definitely seems possible for Lincoln to have white hair at 11 seeing how his Pop-Pop has the same hair and it hasn't been revealed why his hair is white. For all we know Pop-Pop could of had his white hair at a very young age as well.