Bad children and a box of beverage!
D. and F. provided one beverage box with 32 bottles for the weekend party, but one of their four children changed the content of one of the bottles that cannot be detected easily! To punish the children, they decided to permute the bottles and ask the children to find it again until two days later! Unfortunately if one drinks from THAT bottle, he/she will be sick tomorrow for a week, but the children like to participate in the party very much! What is the best strategy for the children?