I'm 21 and like with my parents, so basically earlier today I left the house to go out and took my set of keys with me but didn't lock the door when I left because my Mum was upstairs in the house ironing, my Dad was at work at this time. When I got back home I got a little reminder from my Mum saying that if someone is upstairs and no one is downstairs I should lock the door if I'm leaving the house. From now on I'll take my Mum's advice but was she being a bit OTT or was I being careless in not locking the door.