It is a strange one as "toddle" would seem to be something other than "crawl" as obviously little kids become toddlers once they are walking. I've never in 50 odd years in Scotland heard toddle used to describe someone who's crawling. So you'd expect 'toddle' here to mean walk aimlessly or unsteadily. So Kevin's idea that it might be a worm as in a dragon like monster makes sense.