See an incredible moment when two sisters are reunited after 40 years
In Cambodia, the aftermath of the Khmer Rouge era in the 1970s saw families torn apart, due to a state policy of separating children from their parents during four years in which almost two million people were killed.
Today, many remain separated - like sisters Hong and Bo, separated from their family in 1975.
Channel 4's Krishnan Guru-Murthy travelled to the set of a reality TV show which aims to reunite these sundered families, and the result for the station's Unreported World series is truly moving.
It's incredible.
It's hard not to be moved by the moment the sisters see each other for the first time in four decades - but the mystery deepens when the programme reveals family photos that don't belong to either sister.
If you can handle any more of that emotional rollercoaster, the full documentary, "40 years to find my family", is available on YouTube from 4oD documentaries, clocking in at 25 minutes.
