Chris Pratt and Katherine Schwarzenegger Expecting Baby No. 3

Chris Pratt and Katherine Schwarzenegger are expanding their family … because she’s got another bun in the oven.

Arnold Schwarzenegger‘s daughter is pregnant with the married couple’s third child … TMZ has confirmed.

Unclear how far along Katherine is in this pregnancy … ditto for whether it’s a boy or a girl on the way.

We actually talked to Chris Thursday in L.A., but he didn’t let on about the new addition on the way — instead, he told our photog he’s cool with making the jump from Marvel to DC … if his director pal James Gunn has a role for him in the DCU films.

As you know, Katherine and Chris already have 2 young daughters together — 2-year-old Lyla Maria and 13-month-old Eloise Christina. Chris is also father to 10-year-old Jack, who he had with his ex-wife, Anna Faris.

PEOPLE was first to report the new pregnancy.

So, this makes 3 pregnancies in as many years for Katherine and Chris, and he’s about to be a father to 4. Something tells us Elon Musk and Nick Cannon would approve.