I agree with pp. I'd take your baby, but leave if baby gets too fussy. Babies are a source of comfort for many at a time like this. One of my best friends often talks of the baby at her dad's funeral. My friend was 17 at the time, and was not handling her father's death well. She apparently started freaking out at the funeral, and they were having a hard time calming her down. Someone, and to this day I'm not sure she even knows who, put their young baby into her arms, and this apparently had a very calming affect on her. She says it gave her a strong feeling of peace at a time when she couldn't find it elsewhere.
Now that being said, a fussy, crying baby might have the opposite effect. I'd just make sure you are able to leave quickly. When DS was a baby, DH's grand-mother passed away. We took both kids to the funeral, even 3-year-old DD, but DD was a VERY calm child, who sat well for long periods of time without making a fuss. Had she been a more "active" child, I might have been more reluctant to bring her. As it was, we sat at the back, even though that meant we weren't with family, to make sure we could leave quickly, and unobtrusively if either child got fussy.