Melissa Grice said Tuesday that she bought her daughter's birthday card before the girl died May 20 after a jet-ski wreck on Taw Caw.
She read from the card and released balloons with family and friends Tuesday to mark what would have been Millicent "Milli" McDonald's 20th birthday.
"I think I bought it in February or March," Grice said. "I see a card and buy it if I like them. I had even addressed it for her birthday. I just didn't know she wouldn't be here to see it."
The card read, "Daughter, even though you're not a little girl anymore, I still feel the need to tell you. You are the princess of my heart, the sunshine in my days and the sweetest gift this world has ever known. Love you, mama"
Those gathered also lit candles around a makeshift memorial near the Taw Caw boat ramp going toward Goat Island.
