The Blue Bloods actor took to Instagram on Wednesday to announce the tragic news that his French Bulldog, Lumpy, passed away at the age of 12 with a touching tribute video that featured the pooch, Jenny, and his stepson Evan Joseph.
WATCH: Donnie Wahlberg mourns death of beloved pet dog
Donnie revealed that Lumpy died in May, but he kept the news private because he was on tour, and he wanted the time with his fans to be full of "joy, happiness and love".
Posting a lengthy caption in tribute to his "constant sidekick", Donnie penned: "So many of you asked me about my constant sidekick, Lumpy, during the Mix Tape Tour. His usual playful presence, by my side, was clearly missed by all. Night after night, I was asked. Night after night, I uncomfortably avoided the conversation."
He explained: "I did so in order to allow our time together at meet & greet (and at the concerts) to be a time of joy, happiness and love. Three things that we all needed so desperately after the last few years of sadness, heartache and struggle."
Donnie and Lumpy
Breaking the news, he continued: "So it is with great difficulty that I inform you all now, that on May 18th (on one of the rare days off during the tour) my beloved dog Lumpy, was laid to rest. I know how much Lumpy meant to so many of you. He had become a special member of our Blockhead family.
"He was also a very special and beloved member of my family. His loss was a devastating blow to us all. Especially to me and my son Elijah. Since the day Elijah convinced me (12 years ago) that I needed a four-legged Frenchie friend to keep me company during my time away from home, while shooting Blue Bloods, Lumpy has been by my side — on set, on tour, on planes, trains, boats and automobiles. Even on snowplows!
Donnie and Jenny married in 2014
"He's been a constant loving companion and a loyal friend to me and so many of you who got to know him. To some, Lumpy was a tv star, a rock star and a source of joy. For me — he was all of that and more. He was my best buddy. My family and I will miss him tremendously, as I know you all will too."
Donnie added: "As someone who always tries to find gratitude, even in the most heartbreaking of times, this situation is no different for me. So today, despite the many tears shed while writing this, my broken heart is replaced by a thankful heart.
"A heart filled with gratitude and love for having been blessed with the best friend a guy could ever ask for. I don't mourn Lumpy today — instead, I celebrate his memory. I invite you to do the same. Thanks for the kindness that you all showed Lumpy through the years. He truly was — and will always be — the best! Francis 'Lumpy' Wahlberg."
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