The actor/singer's mum, Katherine Bowen MCIntyre, passed away aged 83 on Sunday (30Nov14).
MCIntyre, who currently lives in Los Angeles while filming U.S. sitcom The MCCarthys, shared a photo on Instagram.com on Monday (01Dec14) of his beloved mother beside his seven-year-old son, Griffin.
MCIntyre wrote, "My mom passed away yesterday morning. In her final months and days she was at peace. Happy to have her family around. She'd laugh and smile and hold hands and hug. This picture is when I last saw her in August. As you you can see, my son Griffin was thrilled to hang out with her.
"Alzheimer's is a horrible horrible disease, but for us, it was bitter sweet. The last few years there was just love and sweetness. You can't be a lily all the time while raising 9 kids. 9 kids!!! She had a strong abiding faith in her God. And I am a product of that faith. She is missed but she will always be with us."
MCIntyre also shared his gratitude for the many New Kids on the Block fans who have supported his mum through the years.
He added, "I know many of you Bhs (Blockheads/fans) have a special connection to her. Over the years, she always thought it was so special of you all to write her and send keepsakes. She'd often send handwritten letters back.
"She was a lovely writer- very witty. Loved a parody - could rewrite a lyric of a standard and personalize it for a friend or co-worker on the spot. And she'd sing it for them too. And her great get away- the stage.... She's singing a song to St. Peter now. I love you, Mama."
MCIntyre has been an ardent supporter of Alzheimer's research and awareness ever since his mum was diagnosed. He frequently runs marathons in order to raise money for the memory-stealing disease, and most notably took part in the 2013 Boston Marathon, when two explosions ripped through the crowds close to the finish line.
MCIntyre, a Boston native, had crossed the line just 11 minutes before the bombs went off.