The Bella Twins have been united together since birth, but with Nikki sidelined for at least three months, Brie is already feeling the impact.

The longest-reigning Divas Champion in WWE history underwent neck surgery on Thursday, and it is considered career-threatening. She'll now spend the next three months at home rehabbing, while a return to the ring isn't guaranteed.

John Cena Not As Open To 'Total Divas' As Daniel Bryan

John Cena, Brie and other family members were by Nikki's side before and after the procedure at the hospital. Cena is also on the mend as he is recovering from shoulder surgery he underwent earlier this month.

While the WWE's resident power couple gets to spend time together healing up at home, Brie is thrust back into the busy schedule that is being a WWE Diva. Brie, whose husband Daniel Bryan is also out indefinitely with a concussion and hasn't been able to get cleared, is already feeling the loneliness.

Brie Bella Hints At Unhappiness In Role With WWE

"Being her tag partner and her sister, it's been hard on me too," Brie told the WWE in a video chronicling Nikki's surgery day, "because I'm so used to walking out with Nikki down the ramp. I feel like I have more anxiety and I'm more nervous than she is. It's just, of course, fearless Nikki."

Brie and Alicia Fox are still together on WWE television, but it's apparent that Brie is feeling the void her sister's absence creates. Nikki hasn't competed in a WWE ring since October, but she came back to win the Diva of the Year Award for 2015 in December.

There is hope that Nikki will be able to compete once again, but for now, Brie is forced to cope with not being able to travel and compete with her.

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