'Teen Mom OG' Cast Member Kristina Shirley Says She Has 'Baby Fever'

Amber Portwood is expecting a baby, but her ex may just be expecting a child of his own [...]

Amber Portwood is expecting a baby, but her ex may just be expecting a child of his own soon.

Kristina Shirley, the wife of Portwood's ex Gary Shirley, dished on Twitter on Tuesday night that she has "baby fever."

"I'm getting baby fever," Shirley wrote. "Watch out, [Gary]!"

Shirley's comment came in response to an Us Weekly article about the latest episode of Teen Mom OG and how there "was a TON of baby fever going on." The article discussed Maci Bookout's desire to adopt and Mackenzie Standifer, who's married to Bookout's ex Ryan Edwards, revealing her pregnancy.

It looks like Shirley wants in on the wave of all the new Teen Mom babies, and her supporters are all for it. They replied to the tweet with loads of supportive comments.

"Come [on, Gary] you are an awesome Dad, just imagine the fun you would have with a son, to share your interests with!" one viewer wrote. "Leah and Emilee would be AWESOME big sisters! I bet they would LOVE it!"

Another fan added, "You two are arguably the one's most stable and ready for more children. Not that you need any random person on the internet's acceptance."

The Shirleys already have one child together, 2-year-old Emilee. Gary also has a child with Portwood, 9-year-old Leah. Shirley has a child from a previous relationship, as well, though she has yet to appear on Teen Mom.

As for when Portwood's baby will arrive, her boyfriend, Andrew Glennon, broke the news on Instagram. The couple's child is expected on May 13.

"Bomb's Away!" Glennon captioned a cute photo. "Little James' due date: May 13th, Mother's Day! One day before Amber's actual birthday. She was born on Mother's Day 1990. The stars really aligned on this one."

Teen Mom OG airs Mondays at 9 p.m. ET on MTV.