Grace, 31, told Conan O'Brien during an appearance on his show that the protective Neeson once offered to help her set an ex-boyfriend "straight" after she told him she was having a tough time with a breakup.
''There was this boy who had really hurt my feelings and was kind of being a hot mess, and Liam was just like, 'Let's set this kid straight,'" said said. ''It was great.''
In a gesture of solidarity for his on-screen daughter, he joined her in a prank call to the guy, with Neeson taking on his tough guy persona to put a little fear into the actresses annoying boyfriend.
"I don't need to say it, but I have a particular set of skills, and I don't want to waste them on you," Neeson is heard saying in an audio recording of the call.
''My man now is just so good to me because look at what hangs in the balance. You know at any point [I could call Liam]. I should call Liam when I get parking tickets, anything... I should be like, 'Liam, could you...'''
— Taken 3 (@TakenMovies) January 8, 2015
Grace confirmed the Northern Irish star's protective nature towards his costar in a Today show interview.
''He's just incredibly protective and lovely, and has a really weird sense of humour.''
Grace and Neeson are once again teaming up for the third and last installment of the action thriller, Taken 3 which will be released in theaters Friday.