Time to bust out the baby Notebook!
A rep for McAdams could not be reached.
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The Mean Girls actress, 39, and Dear John writer Jamie Linden, 37, were first romantically linked in April 2016, and have kept a relatively low profile throughout their relationship.
The pair rarely appear in public together and have yet to make their red carpet debut as a couple.
McAdams was absent from the Wednesday premiere of her new dark comedy Game Night, where costars Jason Bateman, Kyle Chandler, Michael C. Hall and more walked the red carpet at the TCL Chinese Theater in Hollywood, California.
The notably private star previously revealed that while having children was something she’d given a lot of thought to, she wanted to make sure she found the right partner first.
“Part of me is very attached to the idea of having children,” McAdams told InStyle in 2010, adding, “It’ll depend on if I find the person I want to do that with.”