“...get the keys from off the pushchair, put the right key in the door, turn it and open the door,...”
Sounds like they had a deadbolt lock with a key on both sides. This is very dumb and dangerous thing to do. As matter of fact it is illegal in many localities in the U.S.
You should always have a way OUT of your house that does not require a key, on any door. Otherwise you could become trapped in a fire.