I have shared custody of my children with my ex. (It seemed like a good idea at the time.) They are 11 and 8 years old. I just recently found out he has been leaving them home alone while he goes to the shops etc. I have just started leaving our oldest alone for short periods of time by himself and I don't feel comfortable with him having that amount of responsibility. My ex disagrees and says he will continue doing it. AIBU? Even if other parents feel comfortable with their 11 year olds babysitting a younger sibling surely my views should count for something? I am their Mum after all. I think in another year or so it will be okay, but I just think he's too young, and it's not fair on him.