I rarely disagree with Jake,  and I'm not sure I entirely do this time.  It depends  on the whole situation, the  kids, the adults involved, etc.  My gut response is take them to the visitation but not the funeral.  I would suggest leaving them in the the care of someone else instead of you doing it.

And keep in mind one of my oft repeated gems of advice during this time.  People are stupid.  If you start with that expectation everything will be fine.

The situation is awkward, people get tongue tied, often they start talking before turning on the brain.  People are going to say and do stupid things.  Just think "they must be grieving too"  and let it slide.