I have always thought that when the mammal quivers at the breast, the 
breast has a letdown reflex.  In fact, with a baby I recall, he was a little "lazy" 
shall we say, and would just do some quivering eyes wide open and wait for 
that milk to let down.  I have seen the same sort of behavior with puppies, 
kittens,etc.  I may be wrong, I don't remember where I heard of this before 
except noticing it in other mammals, but i think its just a normal reflex most of 
the time, to get the breast to let down.

At other times it could be the baby's jaw getting tired i suppose, esp. at the 
end of a feed.

If baby is gaining and  milestones are age appropriate I wouldn't give it too 
much worry.  Babies are smart, they know how to work the "system" :)

best,
robin

             ***********************************************

Archives: http://community.lsoft.com/archives/LACTNET.html
To reach list owners: [log in to unmask]
Mail all list management commands to: [log in to unmask]
COMMANDS:
1. To temporarily stop your subscription write in the body of an email: set lactnet nomail
2. To start it again: set lactnet mail
3. To unsubscribe: unsubscribe lactnet
4. To get a comprehensive list of rules and directions: get lactnet welcome