Before I proceed to massage your throbbing ovaries with photos of adorable kids, let me explain what I mean by "big, serious" celebrity babies. "Big, serious baby" is a phrase Ami uses to describe babies who are not necessary large in size (although it helps) but have a weighty seriousness to their demeanor. Some babies are super giggly and smiley and then some babies look like they found out they owe $20,000 in back taxes or have just finished reading Angela's Ashes. Personally, I think a big, serious baby is almost cuter than a smiley baby, but let's face it, they're all adorable and I'll take one of each! So, here are some of Hollywood's most big, serious babies, thinking big, serious thoughts.