10 month old just ate a crayola crayon?

My 3 year old was coloring and left his crayons in the floor, I got up to go and put a bottle in the sink, and when I came back I noticed brown stuff smeared all over the baby's face and he was chewing on something, while fishing around in his mouth I found a piece of brown crayon!! he swallowed some of it before I could get it out of his mouth..i know the box says they are not toxic, but do you think he will get sick, or stopped up from swallowing a big chunk of brown crayon?