You guys do realize that children can unlock locks right? And like many situation, hindsight is 20-20. Sometimes you need a higher lock, search the net, there are child proof special locks, even alarms for this type of situation. Because it happens so much.
Parent could have locked the door, and toddler still got out. It happens. And if that is the case, I am sure the parents or would hope the parents will find new locking systems.
Without knowing the full story, I personally am not going to rush to judgement and automatically call out parents has bad parents for this.