Jeannette wonders about a "bite mom" gene. My thoughts are:

You have described a mom who had three medicated births. Birth medications
have profound effects on infant suck, which are compounded and exacerbated
by instrument deliveries, suctioning, separation even for weighing prior to
the first feed, etc.  Sounds to me as if these babies ALL are very orally
defensive. I'd suggest lots of skin-to-skin and massage, and cup or spoon
feeding. The baby seems to want to control what goes into his mouth, and has
only a few tools to do so. Let him - keep everything out of his mouth except
her milk given by spoon or cup until he's less defensive. Her strong
let-down or full breast may also be threatening to him. If she wants to BF
for comfort, try it on a soft breast and only after he's had an ounce or two
by cup or spoon, or when somewhat sleepy.

I assume you've checked the baby for tongue-tie.  And she may have ductal
yeast which would make matters worse.

Linda J. Smith, BSE, FACCE, IBCLC
Bright Future Lactation Resource Centre
Dayton, OH USA
http://www.bflrc.com