Hi!
It could be something totally different, but this has been my experience with my kids.
The only time I had this problem with my kids (I have 4 kids ages 6,5, 2, 1yr) was when their neck was out of adjustment.
I'm not sure if you've ever had your children adjusted by a chiropractor, but it's pretty gentle, and from birth, they are out of alignment just from simply being squished inside of you as well as being pulled out in the case of a c-section and coming through the birth canal too (even in the home birth situations) so that seems to help when they get their neck ajusted.
They seemed to have a hard time turning to one side when nursing and then all together stopped because it just got to be too painful to hold their neck to either side. Just like when you wake up with a stiff neck and can't look to one side or the other, it's the same thing.
I have a wonderful chiro that we use who doesn't do any cracking, he just massages and gently puts their neck back into place.
If you want more info on him, I can get that for you.
I hope this helps. It's happened with every one of my children.
The only other reason my kids stopped nursing was when I was pregnant as you said happened with your other child...check that out too! :)
C.
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