She wrote on Instagram on Wednesday, Oct. 28, "My beloved son, James Wilkie, On this day, you are 18 years old. I marvel at the passing of those years but equally the young man you are becoming."
Sarah continued, "My love for you is an ache and an honor. As you leap toward and into your future, I remain your privileged and steadfast confident and joyful witness to the year ahead."
The "Mama" finished by expressing how proud she is of James for voting in the Nov. 3 election. "Happy birthday my first time voter. I love you so," the 55-year-old actress said.
The sweet, never-before-seen photos showed SJP lifting up her baby in the kitchen. Others showed James bundled up ready for winter, running through a grassy meadow, walking hand-in-hand with mom on a cliff side and jumping on a bed in his jammies.
Bette, Sarah and Kathy Najimy are also reuniting for a virtual, one-night-only charity event on Oct. 30 called "In Search of the Sanderson Sisters: A Hocus Pocus Hulaween Takeover." Bette promised "there will definitely be music" at the reunion—and their iconic costumes, too.
The 74-year-old Oscar nominee is down to reprise her role as Winifred Sanderson on the big screen, telling Fox last week, "They want to make a movie. They've asked us if we were interested, and, of course, all of us said, 'Yeah'... I'm game. I'm totally game."
Sarah has given us hope that the sequel will see the light of day, saying back in May, "We've agreed publicly to the right people, yes, that would be a very, very fun idea, so we'll see what the future holds."