its quite complicated. Let us first examin heisenburgs principle and take into effect that in the quantum universe we can only be in one play simultaniously without in effect bumping into our quantum selves.
If we take this into account, you know my sister, and i know chisme, chisme knows you and i reconize that you two are similar
still with me?
cause now my sister apears with you during the aparent 'date' at the time at which quantumly i had no sister. In affect, when you regard to the event as a statement, it ceases to exist.