It's hard to imagine a situation where regular candies for kids might be swapped and mistaken for cannabis edibles, but Denver was on the look out in 2014. The state put out an official warning prior to the holiday that told kids and parents to be on the look out for candy edibles, which are often shaped and made to taste just like their regular counterparts.
As much as it is true - kids should absolutely stay away from edibles meant for responsible adult consumption - there's no easy way for such a mix up to occur. Cannabis edibles are always sold to those of-age and packaged differently than regular candies. Kids should avoid eating any candy that isn't sealed or packaged in general, and those with candy edibles around children should be sure to keep them out of reach.