Kate McCann: "Shall we let daddy in?"

By The Academic on the 3 arguidos: Locking the patio doors

There is the scene where Gerry returns from work at the hospital, no doubt smelling of flowers having saved so many lives. Kate is in the kitchen with Amelie and Gerry pitches up at the back door with his bike then Kate asks Amelie "shall we let daddy in?"

So what is all this about? Leave 3 kids inside an apartment on their own in PDL with the patio doors unlocked. However when Kate and her two remaining children are at home alone in the kitchen, in their home nestled in the relative safety of rural Leicestershire, she locks them all inside.

What were the producers hoping for us to subliminally feel from this? that Kate has somehow come to learn that doors ought to be locked and she ought to not leave children home alone?

Or are we supposed to think that Gerry McCann cannot be trusted with a key to his own home?
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