Arnett also voices the title character of Netflix's original animated series Bo Jack Horseman. and attended Concordia University, Montreal for one semester, but dropped out.
Turns out, Shia La Beouf, Jake Johnson, and the star are "#Not The Father." Related: Will Arnett Admits To Relapsing On His Sobriety!
While not confirmed, sources say the baby belongs to estranged husband Brian Austin Green.
On Tuesday, Will attended Cinema Con in Las Vegas where he jokingly appeared surprise that he wasn't Fox's baby daddy.
The 45-year-old said : "There are like 50 jokes that come to mind but we live in social media era and I'm not going to say 'em you know what I mean?