The presenter will reteam with Nicky Campbell for the ITV programme, which reunites relatives after vast amounts of time apart.
"If you thought series one was emotional, you've not seen anything yet," she pledged. ''The stories we've unearthed this time round will tug at your heart-strings like never before. Get ready to start stockpiling those tissues."
The first episode of Long Lost Family will focus on ex-professional rugby player Mark Appleson searching for his birth mother and a 71-year-old hoping to meet her daughter after half a century.
Speaking about his recruitment to the format in 2010, Campbell declared: "'I've never been so excited about a show in my career. I have a deep emotional connection with it, being an adopted person and having traced my own birth families."
Long Lost Family airs Thursday, April 12 at 9pm on ITV1.
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