Senior Liberal Democrats have not entered the row which has seen David Cameron back Chancellor George Osborne's comments that the case prompted "wider questions about our welfare system."
Mr Alexander said: "The Philpott case is an individual tragedy. Children have died in that case.
"I think that is where we should let that case lie. I would not want to connect that to the much wider need to reform our welfare system."
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Wednesday will be cloudy with more breezy and wet weather for many of us.