Warning to parents: what you should know if your child is travelling with another surname.

Apparently, I could end up “embroiled in a child abduction case” with my own son just because he has a different surname.

A UK lawyer has warned that parents could become unknowingly involved in a kidnapping case or “be refused past check-in, or turned away at border control” if they fail to take the right documents with them.

It is estimated some 600,000 parents in the UK have been stopped or even turned away at border control.

Australian lawyer Hannah McKinnon, accredited family law specialist at Slater and Gordon, says the crackdown is to do with increased terrorism controls.

“As we see the whole world’s borders clamp down, these issues that weren’t an issue 10 years ago are obviously starting to be more common,” said Ms McKinnon.

English mum Hannah Marshall, 28, was travelling with her daughter Lilly when she was stopped at London’s Stansted Airport after a holiday in Denmark.

“While queuing I went to one desk with my daughter and my partner and his mum went to another desk for passport control,” she told Manchester Evening News (M.E.N).

"They looked at both mine and my daughter's passports then asked me how I knew the little girl and when I said it was my daughter they asked why I did not have the same last name.

"They asked my daughter who I was to her and that's when my partner came over and explained that she's his daughter too and as we weren't married she had his last name," she added.

"They told us that my partner should have taken her through passport control because I would need to prove she was my daughter. They checked my partner's passport to prove she held the same last name and then let us through."

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Ms McKinnon says the problem is unlikely to happen at Australian borders but says travelling parents that have children with a different surname should take a portfolio of documents with them - including a passport and birth certificate.

"As soon as you go off the beaten track they don't understand. That's the problem," she said.

"Anywhere that's not a first world country - you would come up with questions," she added.

The family law specialist says it's best to travel with an e-file with everything on it in case you are challenged.

UK lawyer David Connor, from Woodcocks Haworth and Nuttall Solicitors, told M.E.N. separated families need evidence of approval from the child’s other parent.

"Remember to seek approval from everyone with parental responsibility – this may include grandparents too," he said.

"It’s vital that all evidence marries up and this is where divorced parents are often caught out, particularly women who revert back to their maiden name. A change of name deed will help here, which can be supplied by a solicitor. Take a copy of your child’s birth certificate with you too to prove who you are," he said.

Ms McKinnon says being prepared could avoid an inconvenience when you get to passport control - she has been challenged twice with her own children.