I booked an interconnecting room in Egypt for my DD's 12&10, many years ago.
They had given the room to two pilots, when we got there and they had to have one up the corridor.
The cleaning staff were friendly (wanted good tips) so remembered to knock on our door before entering, their room.
They try to give priority to those with children, but it isn't always possible and if there is a emergency booking, worth lots of money to the hotel, disabled guest needs come first.
I have stayed in hotels were other guests have roamed at night, supposedly going into the wrong room, but we, or other guests have had stuff stolen.
So if you go ahead, I second blocking the door from being opened.
I don't see why you can't have sex in the bathroom, if needs be, or even be risky and use the balcony. I would go with either because I am a cheapskate.
Surely you won't be in a situation that you will be sitting in the room whilst your toddler sleeps? They sleep in their pushchairs on holiday.