'The pain - he was not mine': The trauma of El Salvador baby swap family

To look at Moses Cushworth you would not know that anything has gone wrong.

Moses is a beautiful baby boy. His eyes stare back at you, open, inquiring. He does not cry, does not complain. Just takes it all in.

We do not know if this was how he behaved during the first four months of his life, and nor do his parents Rich and Mercedes.

This is because Moses Cushworth was swapped at birth in El Salvador, given to the wrong mother and father.

"We are overwhelmed, we're happy, we feel safe," his mother Mercy Cushworth says a day after finally arriving back home in Dallas, Texas, with her son.

"I slept the whole night last night. He slept the whole night - overslept today," she smiles, cradling her baby. He's sleeping again as we speak.Baby swapped at birth returns homeIt is a tale that will frighten every parent. A tale of the birth of a son, and of the joy of holding that son to your breast. A tale in which that child, born prematurely, spends his first night on a specialist ward, away from his mother. And the next day, unknown to them, a different baby boy is brought to his parents.

This is what happened to Mercy and Rich Cushworth. They named the boy brought to them that morning in the hospital Jacob, and for four months back home in Texas they brought him up as their own.

But there was always, says Mercy, the nagging, chilling suspicion that Jacob was not theirs. And she couldn't shake it. The boy did not look like either of them, she remembers.

So she decided to take a DNA test.

"I felt like I was betraying him. That was a feeling I had - I am betraying my son," but she had to do it. And it was not her sonThe result of that test was incontrovertible. Mercy says there was a 0.0% chance, according to the test, that she was the mother of the boy she had raised from day two of his life.

It is now that the tears start to roll down her face.

"The pain. The thought that the baby I had been nursing, taking care of, loving him, bathing him, that he was not mine.

"And then I had another thought that came with it - where's my baby?"

He was back in El Salvador with another family who had also given birth to a boy in the hospital that day.

Within hours, Jacob and Moses were swapped once again - this time handed to their biological parents. But by this stage both mothers and fathers had formed a bond with a child that was not their own. It was heartbreaking.

"My lawyer said 'We have to bring the other baby' and I'm like 'What'? and he said 'We've found the other family, you have to hand him in'.

"We barely had time to say goodbye. I got all his clothes and we took him in the office. And we handed him in. And that was the most difficult part of all the situation.

"Then at the same time got our own baby, and that was so happy. And he was smiling."

That was more than eight months ago. And you would have thought that would have brought to an end this emotional tale. Yet it did not.

To leave El Salvador, Moses Cushworth, now four months old and oblivious to the storm surrounding his birth, needed a passport. And to get a passport, he needed a birth certificate.That happened only in the past few weeks.

For Rich Cushworth, this has been the most difficult bit of the whole story.

"Taking nine months to get paperwork for this child has perhaps been the most painful part of the entire process," he says. "It's bankrupted us financially. It's been forced separation - it's just been awful."

When Bernhard Garside was appointed Her Majesty's Ambassador to the Republic of El Salvador he probably did not imagine that his brief would involve helping to reunite a baby boy and his parents.

And yet according to the Cushworths he has played a key part. Rich Cushworth has lived in the US for years, but he is still a British citizen. He refers to Ambassador Garside as "an angel".

Our man in El Salvador probably would not recognise the description, but he does acknowledge the difficulties they all faced.

"What took time was unravelling the legality of all the birth certificates - and making sure the right parents were recorded with the right children."

As for what actually happened in the first place, with the swapping of the babies, he says that officials in El Salvador "have concluded their investigations and found there was no criminal element involved in any of this and it was simply a mistake".

But the Cushworths still want answers. They want to know why this happened, to make sure no one else ever has to go through what they have endured.