Robin Roberts celebrates Amber Laign, her longtime partner,'s successful completion of radiation during her breast cancer treatment.

"Sweet Amber has completed radiation, which is a very important stage of her treatment!" The "Good Morning America"

anchor captioned an Instagram Video Monday showing Laign ringing the ceremonial bell for cancer at Memorial Sloan Kettering Cancer Center.

Roberts said, "We both want to thank you for your good wishes and prayers." We are proud of her and all other

Robin Roberts

Thrivers for their grit, grace, and perseverance during difficult times. This is my #mondaymotivation

The short clip shows the massage therapist reading from a plaque on the wall. She said: "My treatment is over, the course has been completed, and I'm on my way."

After ringing the bell three more times, she took off her hat and jumped up and down. Then, she joined in with many others who clapped for and with her.