There have been reports of Alexa randomly bursting out in laughter and it's creeping people out! Amazon addressed the concerns. "In rare circumstances, Alexa can mistakenly hear the phrase 'Alexa, laugh,'" the company said in a statement. "We are changing that phrase to be 'Alexa, can you laugh?' which is less likely to have false positives, and we are disabling the short utterance 'Alexa, laugh.' We are also changing Alexa’s response from simply laughter to 'Sure, I can laugh,' followed by laughter."
But that doesn't explain Alexa randomly without being prompted laughing.....she just be having a little fun! LOL. I choose to believe that, because that sounds less creepy.