I never really thought about how teaching to share could backfire

I work with two year olds. Yesterday there were two instances where sharing was done in the wrong way. Number one: I gave a child a wet wipe for their mucus. After they finished, another child came over and he had mucus, the first child handed them her wipe. Before I could do anything he was wiping his face. Number two: We've been letting the kids get their own water. Well this is going to stop now. Two kids we're seeing that their friends cups were getting low and they poured their own water into their friends cups. 🤦🏽‍♀️