Gavin and Stacey star Alison Steadman was left shocked and upset during filming for ITV's DNA Journey, as an emotional discovery changed everything for her family.
The actress joins pal and co-star Larry Lamb on the series, which delves into celebrities' ancestry and their DNA.
But Alison revealed on Good Morning Britain on Tuesday that she discovered something on the series that had never been revealed to her family, that left her "upset" and "knocked sideways".
