My twin sister & I were left home alone from around 8yrs old. Mine was due to Mum & Dad running their own business & the shop was open 7am til 9pm every day (7 days a week). Mum or Dad would get home before dinner time though. Its funny how a few of you have said "how things have changed". A bit off subject here but when mum & dad bought their house,it had a swimming pool without a fence. My sister & I were 7yrs old & never learnt to swim. We would come home from school strip off on theback deck & jump in the pool. We tought ourselves how to swim!! Lucky to be alive if you ask me LOL But I could never let my kids do that! (things have certainly changed!)

I cant see me leaving Brianna home alone at 8yrs old, but I wont know until I get to that age. She is very mature for her age & very trustworthy following rules etc so I dont know

I guess it does depend on the child, you said he's not very independant.... on that alone he shouldn't be left on his own. Thats not fair to him.

I hope you can convince your SD it's not right.