The Scorpion star, 37, revealed on Thursday that his second child with wife Kelsey Mayfield Porter will be a girl, breaking the big news through social media.
In the photo, a University of Texas at Austin mini cheerleader’s uniform hung alongside a similar University of Nebraska – Lincoln dress.
“Baby girl is gonna have a tough time deciding who to cheer for, but we’ll love her no matter what school she chooses…right, @kiwiporter?” wrote Porter.
Want all the latest pregnancy and birth announcements, plus celebrity mom blogs? Click here to get those and more in the PEOPLE Babies newsletter.
The couple previously opened up to PEOPLE after McCoy’s birth, revealing that Kelsey had been diagnosed with Huntington’s disease – a neurological condition in which the cells in the brain break down over time – before getting pregnant.
“As soon as we found out Kelsey had Huntington’s, she said, ‘I want to have a kid right away,’ ” Porter told PEOPLE. ” ‘I want to have as much time with our kids as I possibly can before Huntington’s starts to take effect.’ ”
RELATED VIDEO: The Friday Night Lights Cast Was Banned From Playing Flag Football
Kelsey, whose mother also has Huntington’s, discovered that they could undergo extensive fertility treatments to prevent passing the disease on to their future children.
“Because I have Huntington’s, any child we have has 50/50 chance of having it, so to eliminate that, we did in vitro fertilization,” Kelsey explained at the time. “But we did preimplantation genetic diagnosis, which they test the embryo. They tested all our embryos for Huntington’s and [McCoy] was the first little baby who made it all the way.”