File this under things that make you go hmmmm....
In fact, the report alleges, they were hookup buddies.
Two and a half years ago in September 2015, a source told The Sun, the Victoria's Secret models made out with one another at a LOVE magazine party at London club Loulou's.
"Bella and Stella were at a table in the corner but only had eyes for each other," the source said. "They were kissing passionately and looked to be really into it and having a lot of fun."
Photos show Stella and Bella attended a LOVE magazine and Marc Jacobs London Fashion Week bash at the hotspot on Sept. 19 that year along with singer Jesse Jo Stark and Frances Bean Cobain.
Back then, the source added, "Bella wasn't the star that she is now. She's likely to be far more discreet now."
Before that in the summer of 2015, the international model -- who was born in Belgium to Northern Irish parents and later raised in New Zealand -- was romantically linked to Miley Cyrus, 25, who has identified as "pansexual." That relationship occurred before Miley got back together with Australian actor Liam Hemsworth, 28.
Bella and Canadian star The Weeknd, 28, broke up in November 2016 after more than a year of dating. She hasn't stepped out with anyone romantically, at least publicly, since then, though she and the singer-producer reportedly spent time together again after his fall 2017 split with Selena Gomez, 25.
Stella and Bella have been friends for years. In February 2017, Bella playfully kissed Stella on the cheek as a photographer snapped away during a Tommy Hilfiger fashion show afterparty in Los Angeles.
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