In this case the baby is the child of an american citizen, so I have no problem with it being allowed to stay. If Mama can't stay, that's just too bad. But still, if you're married to an american and have an american child, I would think that would get you a green card, as long as it wasn't a sham marriage.
And that's it, then. A few judges and bureaucrats get intent on enforcing "the letter of the law" in isolated cases even when the particular letter is bogus and allow great gouts of violations to pass unhindered.
I wouldn't even qualify a "sham" marriage unless a divorce occurs pretty much immediately on entry. I'd hate to leave it to bureaucrats and judges to define a sham marriage.