Last night 12yo ds asked if he could take his 6yo sister to the shops today - company for him because he wants to buy me and dh a little present for Christmas. He's a mature amd sensible boy. He's allowed out on his own, we've left him home alone for a couple of hours (max) occasionally and he regularly catches the bus home from school (a 20 min journey). The shops are a Tesco Extra precinct, about a 5 minute walk away. They have to cross one road on the way, which isn't massively busy, and there us a crossing they will use. He has a phone to contact us on. 6yo is also pretty mature and aware of dangers, not a risk taker. They can argue and get a bit silly together as siblings do, but generally when I've had to leave ds in charge for 5 mins while I'm on a work call for example he helps her out if she needs it, baths her to help out sometimes and is fiercely protective of her. I have no doubts about his maturity and ability. But I worry that if, for example, anything bad were to happen, he would blame himself. This is something he really wants to do, and is very sweet (he's confident, but having her there gives him more confidence, same for her) but genuinely don't know if iabu for considering it.