Paul Walker was Vin Diesel's "other half".
Vin Diesel
The 49-year-old actor - who has Hania, nine, Vincent, six, and Pauline, two, with his partner Paloma Jiménez - was devastated when his close pal and his 'Fast and Furious' co-star Paul passed away in November 2013.
He said: "[His mother said to me], 'I'm sorry, I'm sorry, I'm sorry.' And I said why? Why are you saying you're sorry to me? And she said, 'Because you lost your other half.'
"At that moment, it was like, I had just realised - she was telling me something that I wasn't even aware of. She was telling me ... I wasn't aware of how profound the loss was."
And understandably Paul's death has been hard on all of his loved ones - family and friends.
Speaking on SiriusXM show 'Conversations with Maria Menounos', Vin added: "We're probably all a little guilty of not telling people how much we love them while they're here.
"His mother then told my mom - and my mom just a month ago told me this - his mother told my mom, 'Love your child. Just love your child.'"
Meanwhile, Vin previously admitted he is still "reeling" from the death of Paul.
He said: "I'm still reeling from the loss, the idea of continuing along without my brother Pablo and what that felt like and the complexities of that.
"If I ever had a concern of something I would call him. And I don't have that call now and I don't have that person that's dreaming up the impossible with me. One of the things that makes this film so magical, the relationships are so powerful that they bleed off screen ...
"There wasn't a second we made this movie, not a minute, not a day that went by that we weren't thinking about our brother Pablo. How to bring him into the movie, how to represent him and how to make something that he would be proud of. Pablo, I hope you are proud tonight."
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