A pair of New Jersey identical twins were seen smiling together with friends in a photo posted to social media less than two hours before one sister allegedly stabbed the other to death.

Anna and Amanda Ramirez, 27, were pictured grinning and palling around with two friends in a photo posted to Anna’s Facebook page just before 3:45 a.m. Saturday.

“You know the vibe,” read the caption on the snap.

But less than two hours later, cops found Anna lying unconscious and knifed on the ground outside her Camden housing complex, prosecutors have said.

She was pronounced dead at an area hospital, and her twin, Amanda, was arrested and charged with aggravated manslaughter.

A motive for the alleged sororicide remained unclear, as mourners and family struggled to make sense of the slaying.

“Murder is always horrific. … But this…,” wrote one horrified commenter on the Facebook post. “Completely unnerving.”

The twins’ distraught relatives refused comment to reporters at a family home on Tuesday.

But Anna was mourned in an obituary as a dedicated nursing assistant and family-first mom of three — as well as the “dear sister of Amanda.”

“She loved to spend time with her family and was a devoted mother,” read the remembrance. “Anna had a special bond with her grandparents and enjoyed family dinners and weekly time hanging out with her sisters.”