Us broke the news back in May that Bilson, 33, and the actor, also 33, were expecting a baby.
So it's probably easier to fall for a fellow actor, as most normal Joes won't hack the whole "partner snogging someone but it's totally cool because we're acting" thing.
PHOTOS: How stars worked around their baby bumps Bilson and Christensen first met on set of the 2008 film and got engaged in December 2008.
They quietly called off their engagement in August 2010, reconciling three months later.
Earlier in the day, she was seen in a full-length sheer maxi dress with a purple floral print throughout for her appearance on Good Morning America.
The frock was paired with tan Alaia heels for the early morning appearance.