Lucy Greenwell

It's 35 years since Jess was discovered on that verge, but it's at this moment, Jess's saliva sealed in that plastic vial, that something unstoppable begins.

Six weeks go by, an email arrives.

Your DNA has been processed and it's ready to view.

She logs in and there's something she notices straight away.

It's a surname.

The surname of someone who's also sent their saliva to the site and who shares enough DNA with Jess to make them distant cousins.

This is a pretty strong indication that she's somehow related to the nanny.

DNA doesn't lie, after all.

A serious genealogist would probably want to rule out some other relatives with the same name before jumping to conclusions.

But it seals it for Jess.

Three pieces of evidence now.

The nanny rumours from back in the 80s.

The brother from across the country with his suspicions.

And now this, an identical surname in her DNA results.

She's sure now.

And after researching this story for a year and getting a genealogist to talk me through Jess's DNA results, I am too.

The nanny who said she'd found Jess is in fact her birth mother.

Jess thinks back to that Facebook conversation years ago.

It's an understatement to say that Jess feels hurt by that lie over Facebook.

She sees it as a second rock-hard rejection, an echo of the first.