At the time of the 2010 general election, the Conservatives promised a transferable tax allowance worth around £150 to married couples.
The Liberal Democrat leader Nick Clegg ridiculed the proposals as "patronising drivel that belongs in the Edwardian age".
His party later secured a provision in the coalition agreement allowing them to abstain from voting on the issue.
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Brad Treat, 38, was killed on a trail in the Halfmoon Lakes area of the Flathead National Forest, just outside Glacier National Park.
Appeal judges are to decide on Thursday whether a woman can use the frozen eggs of her dead daughter to give birth to her grandchild.
The £70 million F-35B jet arrived at RAF Fairford in Gloucestershire, two years after engine trouble postponed its first scheduled visit.