I had a really terrifying moment this week when I came downstairs and could not find my 2.5 year old DD in the house. (I had been changing the baby's nappy upstairs and the toddler had run off, and I hadn't followed immediately as she normally plays quite safely by herself.) After a minute or two I was horrified to find her in the garden, having unlocked the back door which had definitely been locked and the keys hadn't even been in the lock! She's a tall girl so she is able to reach the handle on most doors, however I didn't think she had the manual dexterity to put a key in a lock and turn it. Now I keep the key well out of reach.
Has anything similar happened to you, where you didn't even realise something has a risk until it happened?