Jump Start Fermentation

[ezcaps_phpbb3_import2]

My dad has told me that transferring some of the beverage from one bottle to another that is just beginning to ferment, will "jump start" the fermentation process. Is this true? And if so, how much should I add per 2-liter and ill it matter if the beverages are different flavors?

Your dad is referring to using an existing fermenting beverage to a new one as a starter. Yes it works, very similar to reusing yeast. It may effect flavor if they are different recipes. Could be good, could be bad, could be neutral.