Our smells of next door's garlic - help!

[doodleboo]

Over the last couple of weeks our house has started to smell really garlicky (we haven't cooked any garlic!). It especially smells upstairs if the the bedroom doors have been shut for more than an hour or so, but we are now able to smell it downstairs too.

We live in a terrace with neighbours on both sides, both sets have just come back after some time away.

The smell is now really strong and horrible and i wonder if it can be something they're cooking leaking through the walls but who eats garlic every night? I can't see how it would make it through.

The other thing is that our boiler has recently been replaced (and passed an inspection) and someone had posted on the internet that it can be a sign of a gas leak - any truth in this?

Or do we have some secret and terrible mould somewhere that smells?

Please help!

[doodleboo]

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