MP has three family members on his staff list

When it comes to keeping your family close, Ian Liddell-Grainger, a blue-blooded distant relative of the Queen, could teach other MPs a trick or two.

The latest update to the Commons staff register reveals the Tory representative for Bridgwater and West Somerset has not only put his wife to work in his office but also secured Westminster passes for his two eldest children.

Mr Liddell-Grainger – 336th in line to the throne – is one of nearly 30 MPs to register relatives as staff but the only one of the current crop to register more than one family member.

A spokeswoman for Mr Liddell-Grainger confirmed that while his wife, Jill, did work for the MP, his two eldest children, Peter and Sophie, were only on the list because they had Commons' passes which permitted them to enter the building when they visited their father. "It's so that they can come in and out of the building so he doesn't have to keep coming down to let them in," explains his office.

The Independent Parliamentary Standards Authority (Ipsa), which imposes a strict rule forbidding MPs from employing more than one relative, says it is not concerned about the set-up as it has no record of the Liddell-Grainger juniors being paid.

Other MPs who have a relative or namesake in the register include Hugo Swire, Margaret Beckett, Hilary Benn and Chris Grayling.

But the true scale of Westminster nepotism is obscured by those MPs who pay relatives who may not share their name or are not related by blood.

Derek Conway's two sons, Henry and Freddie, who earned more than £80,000 while working for their father, was the first of the expenses scandals to hit the Commons, three years ago.

Mr Conway was ordered to repay £17,000 after watchdogs ruled Henry's salary of £10,000 for an 18-hour week was too high. They also said Freddie – then a student – had been "all but invisible" while working for his father.

Earlier this year Ipsa stopped short of introducing a ban on employing relatives but limited the practice to one family member per MP.

Much of the new expenses regime, outlined by Ipsa in March, was tougher than expected and will see the maximum amount handed to MPs cut by almost a third. Those needing second homes will have to move into rented one-bedroom flats, while no expenses will be paid without a receipt. "No ticket, no laundry," said Ipsa's chairman, Sir Ian Kennedy.

But the key concession to allow the employment of wives and children, described as "connected parties" under the new rules, was at the time criticised by both Sir Christopher Kelly, who conducted the wide-ranging review of the old system in the wake of the expenses scandal, and John Bercow, the Speaker of the Commons.

The decision also ignored Ipsa's own consultation on the issue, in which 59 per cent of public responses demanded a ban on the employment of family members, with only 22 per cent backing the practice. But Sir Ian, who was lobbied by MPs, said Ipsa had been convinced by the "quality" rather than the "quantity" of responses. Sir Christopher described the U-turn on employing relatives as "a mistake" that should be reversed as soon as possible. All three main party leaders had backed Sir Christopher's proposals.