By the way, here is what she recommended for him. He has had two doses of it so far. :)
(This photo thanks to http://www.pronto.com)
Toddlers that were vaginally born and/or that are breast fed have a higher amount of probiotics already in their system then toddlers that were delivered via C-section and/or formula fed. Alan was both vaginally born and breast fed for almost eight months. When a baby starts eating solids, the bacteria begin to increase.
(This photo thanks to http://www.findmeacure.com)
However sometimes when toddlers are prescribed antibiotics, it decreases the amount of probiotic bacteria in their systems. Overall, a toddler's digestive system is still developing, and probiotics can help keep everything healthy and more immune during the process. Introducing probiotics to toddlers (even if they're not sick like Alan), will help prevent and treat diarrhea. The bacteria can also help with lactose intolerance. It breaks down the milk sugars which makes it easier for them to digest.
I will continue to give Alan probiotics after he's recovered from his stomach flu, but only once a week most likely. The bottles are around $25! We will try to experiment with yogurt based probiotics after he feels better, because he barely tolerates yogurt anyways. We will see how that one goes lol. :)
A big thanks to Gerber, Parents, eHow, and 1stProbiotics for all the information I learned.