Halsey is grieving the sudden death of her beloved 5-year-old dog, Jagger. The 27-year-old singer shared adorable photos of her precious pet, whom she considers her "first love," and memorialized him in the caption.

"Before I had a dog of my own, I would hear people mourn their pets and think 'it's just a dog…' well I couldn't have been more wrong," Halsey, who uses the pronouns "she/they," wrote.

"I got Jagger when he was just a few weeks old," she continued. "I sometimes thought about him passing. How would it feel? Well, he'd be old and rickety and grumpy by then. We'd spend the last few years giving him extra ice cream and lazy sunbathing days that he loved when he was too old to run in circles. I knew it would hurt and I feared it immensely, but I was at peace that we’d have many more years together and he'd have a long good life."

Halsey noted that sadly, things didn't turn out that way for her beloved pet, who was a pit bull mix named after Rolling Stones legend Mick Jagger, as per Page Six.

"Jagger was 5 years old and yesterday we lost him to a progressive condition called Myelomalacia," she explained. "It is sudden and uncommon and unfair with a catastrophic prognosis. Within 3 days my beautiful baby boy went from chasing imaginary birds around the yard and laying in my lap turning his ears up at the sounds of Sesame Street, to having paralysis spread through his body by the hour."

The "Without Me" singer said his death was "sudden and shocking" and that she hasn't had the time to process everything yet.

"I don't know why I'm sharing all this besides to just say love your pets every single second because anything can change in a moment," she added. "My very first love, who taught me how to be a mommy. My sweet, sarcastic, so very human boy. Every single person who had the privilege of meeting jagger will never forget him. He was that special."

Halsey then shared some advice to those who don't have pets, writing, "If you're reading this and you don't have a pet, you might be thinking 'it's just a dog.' Like I maybe used to. But I can tell you you're wrong. So f----ng wrong."

Halsey
Halsey is pictured arriving at the iHeartRadio MuchMusic Video Awards (MMVA) in Toronto, Ontario, Canada on Aug. 26, 2018. REUTERS/Mark Blinch

"It's the most visceral loss I have ever felt," she added. "Like the absence of a vital appendage. Every single second of my day that once revolved around his little habits and routines is now full of just emptiness and silence. If you loved Jagger along with me, thank you for giving him the best life the bestest boy could have ever had."

Several people took to the post's comments section to send their messages of condolences to the singer. Many also sent their love and strength to Halsey to help her cope with the devastating loss.