I think you are doing right ignoring him until he stops barking, he will eventually realise that barking = ignoring!
BUt- he might be barking more for attention because he knows he gets a treat for stopping?
I would get him in a down and get your partner to wait outside until the noise has stopped? Then greeting your partner would be the reward?
Also if you son can get him to do the same when you get back from shopping??

My pair get hyper when I get up/home from town/oh gets home I just stick them in the garden to toilet then wait until they calm down before giving them attention.

How about teaching your dog a trick to do once someone comes home? Tricks when taught properly requite alot of comcentration and most dogs cannot bark and concentrate on a trick at the same time.

I had a friend with a grat dane and he barked at visitors but she taught him to carry his fave toy and well you can't really bark with a toy in your mouth!

xx

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