Oh man that is one funny story, Thanks for sharing. That may truly be one of the worst lies ever told. The lie was way worse than the actual crime. I guess in your defense at 6 - 7 years old cognitive reasoning skills are not very well developed or your just a terrible lair (which is a good thing). I don't think I ever told a lie quite this terrible.
Your mom is classic, she slapped you after what 20 years, Haha.