The 38-year-old shared a black-and-white picture on Instagram of the former couple's son Josey, 5, with a thumbs up surrounded by pictures of him with his mother.
"Today…A year ago we laid you to rest. I still can’t believe it. The year has flown by, so fast that it doesn’t seem like it’s been a year at all," the Big Sky star began the post.
"Our boy has grown so much. He’s such an explorer, so inquisitive. He’s sweet, so funny, and his laugh always lights up the room," the actor continued. He’s an intuitive soul to say the least."
"To know him is to love him, everyone that meets him is always smiling. He’s doing ok. He’s such a resilient strong kid. He misses you but knows he’ll see you again, and the invisible string is something that’s helped us out during this ever-evolving transition of your time with us on earth that was unfairly & for reasons we’ll never understand cut short…too soon…" Dorsey added.
The Justified actor explained that July will probably be difficult for the next few years and that he struggles to see photos and "still haven’t been able to read or watch anything…"
"The thumbs up…only Seemed right," he wrote. "I remember the first time he did it back to you. At jujitsu, you gave him a thumbs up and he returned the gesture…it was so sweet."
"Fly high, Rest In Peace, knowing he’s doing 👍 ok…he’s being raised right, and he’s got a lot of family and people around him that love him, and you. 🖤💔💙🖤," Dorsey added.
"For everyone out there that’s gone through similar events of loss…you know there’s not really any words that make it better…we know some days are better than others…but know our hearts and energy are with you. We keep going, because that’s all we can do while being as strong as we can be. 🙏❤️❤️❤️❤️," the post concluded.
Fans reached out to send their support and tributes.
"Beautiful words from a clearly dedicated and loving Dad ❤️," one fan commented.
"❤️ she’s proud of both of you," another wrote.
"always missed, NEVER forgotten. 🤍," a third commented.
The Glee star was reported missing on July 8, 2020, when Josey was found alone on a pontoon on Lake Piru in Southern California. Her body was recovered from the lake on July 13. She was 33 years old.
Rivera’s sister, Nickayla, then reportedly moved in with Dorsey to help raise Josey.
In light of the anniversary, several family members, friends and fans have been offering tributes.
Rivera's mother Yolanda Previtire made an appearance on Good Morning America and said Josey "misses his mom" and often "recalls their life together." "It's almost like we're feeding off each other and lifting each other up," Previtire said of her grandson.
Earlier this month, Glee costar Heather Morris got a tattoo in memory of her friend, which read "Tomorrow is not promised" which is a phrase from one of Rivera’s final tweets.
"It hasn’t gotten easier to write a caption. You are the brightest star in my eyes, Naya Rivera. I’m so grateful GOD LAYED A HAND and brought us together as best friends, mom friends, scene partners, and everything in between," Morris wrote at the time.