Airstrip One

Question

Does anyone know how Iain Duncan-Smith keeps two houses in London and manages to send three children to (expensive) Public Schools on a backbencher's income? I realise that there might be money in his wife's family (Cottesloe) - but are they rich as well as posh?

His entry in the register for Members Interests reads (for remunerated interests):

Occasional journalism, broadcasting and lecturing.
Business consultant to Arlen PLC; sale and marketing of manufactured goods.
Business consultant to Wicksteed Engineering.

Am I missing something here?

For a retraction, click here.