one year old taking 4 hour nap??

momma

my 13 month boy has started taking a 3-4 hour nap everyday. he still wakes once a night to eat but he just started with the super long nap in the middle of the day. growth spurt possibly? he's already the size of a 2 year old i couldn't imagine him getting even taller! any other mommas know what might be going on?