Everett played in all four December games, keeping a clean sheet in two of them and even grabbing an assist against Birmingham City.
Molly-Mae Sharpe latched on to Everett's clipped pass in behind, and lofted the ball over the goalkeeper to give Palace a first-half lead against the Blues.
It was a typically dominant display in defence throughout the month, with Everett standing out in defensive stats like tackles, duels won, and interceptions.
Speaking about her award win, Everett said: "I think throughout the month it could have probably gone to anyone, but it's quite nice to have some recognition, especially from the fans who have been backing me throughout the season!"
When asked about her favourite moment from December, she said: "I would say playing against Arsenal in the quarter-final at Sutton.
"Obviously, unlucky with the result, but I think it was a great day for us, a great performance."
Palace's captain won the vote with 33.0%, marking her first Player of the Month award win since October 2024.
Abbie Larkin was close in second-place with 28.4% of the vote, with Kirsty Howat rounding out the top three with 19.3%.
You can view the result of the poll below!