My 2 year old son has diarrhea...what can I give him to stop the diarrhea?

No stopping. Diarrhea in a toddler is extremely exhausting and I can understand wanting to stop it, but that is rarely the best plan with kids. Hydration is 1st priority by giving baby plenty water/liquids to drink. Making sure that the diarrhea is due to a not-so-serious cause, is best to do by getting a doctor to see your kiddy if diarrhea lasts longer than 12 hours, or if you see any bloody stools. Be safe.