Cold water

I do drink cold water like bubble tea etc throughout my pregnancy journey because of the hot weather which I cannot stand 😅 Not sure what your mil said is true but this kind of things depend on your own beliefs. I personally don’t believe it. My baby is out and have been doing quite well. No hard time for my baby. If you are worried, you can just drink it moderately and not overly. Or try to minimise as much as possible like once a week or two weeks.