It gets very tiresome finding yet another newspaper story in the "You couldn’t make it up, could you?" category, but, here we go again.

Two English sisters have shared a home for years. It has been a real family home, serving different generations. In it, they have cared for various elderly and frail relatives over the years, provided hospitality, built up the links that help to form family networks.

If Joyce and Sybil Burden had proclaimed themselves lesbians and formed a “civil partnership” they would get a massive advantage: when one of them died, the other would receive the whole of the property, tax-free. But they are not lesbians and have no wish to pretend to be. They have a normal and natural bond: they are sisters. So, under our tax laws, when one dies the other will have to pay a massive 40 per cent tax on the property if she wishes to remain living there.

Daft? Of course. Unjust? Undoubtedly. So the sisters took their case to the courts – and eventually to the European court. And now they’ve had the final ruling: they do not qualify for any tax benefits as their situation cannot be compared to marriage or a civil partnership -- in short, because they are not lesbians. So the inheritance tax must be paid in full.

“Rather than the length or the supportive nature of the relationship, what was determinative was the existence of a public undertaking, carrying with it a body of rights and obligations of a contractual nature,” the court piously explained.

Now, I could just about take this if the tax ruling referred specifically to married couples. Marriage between a man and a woman, who normally will have children of that union, is the foundation of family life and hence of our community and our country. It makes legal and financial sense to give it special status.

Oh, I know not everyone is married with a nice bunch of children. We don’t all fit a neat pattern. And every law, however well founded, will create some anomalies. But a just and stable society requires that the law notes the biological reality and the truth about our human condition: children are born of a male/female union. People have a right to know who they are, to have a name and to belong to a family, aware of who their brothers and sisters are. Marriage ensures this, and giving marriage a legal form and status protects us all, including the unmarried.

As soon as the nonsense began about pretending that lesbian and homosexual activity could be given status as a form of matrimony, the link between law and biological reality, between official pronouncements and the truth about our human nature, was snarled up. We’ve now got nonsense.

Two women with an actual family bond have to be treated as though they are complete strangers for legal purposes, while two others who have – perhaps only briefly – engaged in some form of sexual activity together and marked this with a celebration, would be given a special and legally-protected status.

No, this isn’t a diatribe against homosexual or lesbian liaisons. It’s a plea for justice and common sense. Until fairly recently, the cry was that sexual activity was a private matter: “What people do in the privacy of their own bedroom is no concern of the law”. Just so. Let’s have no special status for those proclaiming that they have a “same sex union”.

Inheritance tax is in many ways unjust, and overdue for reform. Ditching the special status given to those who have established a civil union is an obvious component of any reforming plan.

Joanna Bogle writes from London.