A strand of grey hair in my 18 month old head

Tasmina • Can't wait to meet my baby boy in April 😍

Hi all, I just gave my baby boy a hair cut and found a strand of white/grey hair.this freaked me out and like always I googled it and it freaked me out little bit more as this could be related to vitamin deficiency or thyroid issue.i will mention this to the doctor but in the mean time do any of your baby have this or any feedback would be helpful. Thanks a lot in advance.