Michael's post was flooded with support from Mary's many fans.
"She can’t be stopped!" exclaimed her daughter Martha.
"Carbs and confidence," stated another.
"MARY’S THE BEST CHICK OUT THE REST," a third stated.
Ever since Martha and Michael's TV wedding, Mary has been one of the couple's biggest fans - even though she was thinking of the "worst case scenario" to prepare her daughter.
"Michael and Martha I just want to say, you guys have come so far," she wrote on Instagram back in January.
"If I went back five years ago and told you both that you will be going on a show MAFS and you will meet someone. You would just laugh, but here you both are, going onto three years. Amazing, you have both added the missing link to each other and are now totally complete. Michael what a great story to tell your kids How I Met Your Mother.
"Martha even tho you never wanted to go on, look how happy you are today. Enjoy the journey, may the force be with you."
She may have only been on for one episode but Mary has already become an instant fan favourite.
Along with the other intruders, she spent 24 hours on a plane and iconically yelled "I don't want to spill my wine!" when "turbulence" hit.
"You are literally the ONLY reason I am watching this season," one fan wrote on Instagram.
"So damn eager to see you rock the BB house. They are not going to know what hit them. Let loose @maryykala. My money is on you," another noted.