Will there be a happy ending as this series comes to a close?
The final episode of the series follows two families desperately searching for their loved ones before it's too late.
Derek, 73, found out in his twenties that he had a half-brother, the result of an affair his mother had during World War Two.
But he promised his mum he wouldn't search for him while his dad was still alive.
In 2014, his father passed away and Derek immediately began his search to meet the brother he's constantly thought about for more than 50 years.
We also meet 53-year-old Ann, who is searching for her mother to answer some of the questions she has about her heritage.
'I want to know where I am from but only my mum can tell me that.'
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