"There was always moments of child-like laughter…" the 46-year-old actor wrote. "We had accomplished so much by 2013. P.s. The complexities of Brotherhood, and the painful void...of it's absence."
Alongside the heartfelt message, Diesel posted a picture of the "Fast and Furious" co-stars laughing during an impromptu snapshot.
Diesel has been vocal since the Nov. 30 tragic death of Walker. Two days after, Diesel visited the site of Walker's fiery crash and followed a private memorial service by addressing the crowd with the help of a police car speaker. "If my brother were here right now and he saw all of the love you are bringing here," he said.
"If he could see for himself that all of you have shown up to show my brother love… at this hard time his family gets to see all of you show the love that you've shown Paul," he added. "It's going to stay with me forever." Diesel also shared via Facebook that he immediately went to Walker's family's home after hearing the news of his passing.
Walker died at the age of 40 from combined effects of traumatic and thermal injuries in Southern California after his friend, Roger Rodas, crashed a 2005 Porsche Carrera GT into a lamp post. Walker's remains were released to his family last month.
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