Flying with a baby

Hey all-

I am wondering what the thoughts are out there on flying with newborns.
Here is my situation. I have a 2 1/2 month old who is healthy. My
father-in-law wants to fly us from Des Moines, IA to St. Paul, MN next
weekend. I think that the trip is around 1 hour. I have done a little
searching around online and have not found a whole lot so far. From what I
have found, it seems to me that the biggest issue to consider is the noise
of the airplane and hearing protection for the little guy. Other
considerations are the altitude of flight (I assume we will stay under 5000'
flying VFR), speed of decent and restraint within the airplane. There would
be four adults in a cherokee so I suppose mom would have to hold him on her
lap.

Any thoughts, suggestions or experiences would be welcome.


Thanks!

Jeremy