When I was a kid, it was entirely normal for my parents to leave my older brother and me at home alone for long stretches of time. While they didn't leave us alone overnight until he was well into his teen years, we spent many days and evenings left to our own devices, and I was occasionally left entirely alone when I was nine or 10.
I'm not sure at what age I'll finally feel comfortable leaving my son and daughter unattended, but I can tell you it won't be that early. For the record, some states have laws saying it's perfectly fine to leave kids as young as eight or 10 home alone, and I always loved the freedom and appreciated the trust.
But sorry, kids, you're not staying home without us parents any time soon.