Molly stutters sometimes as well, but it usually means she is just talking faster than she can think... She stutters a word for a few seconds until her brain catches up and she can spit it out.

As the others have said, stutters often come and go, so give it a little time. If it becomes a problem, see your GP and get a referral to a speech pathologist, and they will probably be able to give you some exercises to practice to try and nip it in the bud nice and early.