I'm wondering about that too, Heather. It might be to just throw us off, knowing that she and Philip were "together" and then just assuming he's the father of her baby, which she is presumably keeping secret for now.
So, I got to thinking after reading a little blurb from a blind item, from I think Serial Scoop, that said something to the effect of: a returning character's storyline was changed from what was originally planned (story involving 3 characters from her past) to a storyline involving a former rival and mysterious man. My speculation is that this item is about Chloe and she was to be involved in story with Belle, Shawn, and Philip (or perhaps Brady) and instead will be involved in the Nicole/Deimos situation. Now that it's been spoiled that she and Philip were together at some point and knowing that Deimos was involved in the thing with Philip's troubles in Chicago with that gal that overdosed in his hotel room I'm wondering if Chloe and Deimos had some sort of tryst and he is the father of her baby! See, that would be shocking and yet still fit in with story that currently exists and/or has already played out onscreen.