Aslaam alaykum brothers n sisters

My inlaws wana celebrate my sons birthday mashallah hes turning 1 year old next month and my husband totallly desagrees in birthdays bt his family are really into birthdays n celebrating i wana no if iys allowed to celebrate birthday if not i need proof in the hadith so i could show my family plz...my mother inlaw says thr is nuffn wrng in cutting cake without candels and cooking food but bfre i take a step i wana no if its permissable

Jazakallah