R.I.P., Sammy. Justin Bieber is mourning the loss of his beloved pup, Sammy, and he's sharing a vintage photo of the two of them together.

"R.i.p Sammy," the 'Home to Mama' captioned the sweet Instagram pic, using several crying emojis. "You were the best puppy ever."

As fans immediately began trending #RIPSammy on Twitter, many recalled a throwback video from 2009, in which Justin talked about his sweet friendship with Sammy, a brown and white Papillon. You can check out the clip below.

"We moved to a city where we didn't really know anyone, and I kind of wanted a friend," Justin recalled at the time. "And Sam was kind of like that friend."

We know just how hard it is to lose a pet -- they're members of the family, after all -- so our thoughts are with Justin during this difficult time.

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