"Happy Birthday to my big brother" ...
That's how Kim Goldman began her letter to her late bro Ron Goldman on Tuesday -- while reflecting on his life 25 years after his death.
"You would have turned 51 today - just insane to think about all of the years lost, absolutely breaks my heart," Kim wrote in a note posted on social media.
Of course, Ron was brutally murdered on June 12, 1994 ... when he was only 25-years-old.
At the time of his death, Ron was working as a waiter at the Mezzaluna Trattoria restaurant in Brentwood and had gone to Nicole Brown Simpson's condo to return a pair of sunglasses that had been left at the eatery earlier that day.