Does Breastmilk Go Bad In The bosom? All you need to know

Recently, during a discussion, I heard for the first time that breastmilk goes bad (becomes sour) in the bosom if a nursing mother doesn't breastfeed for a long time say 6-7 hours.

As I tried to argue that it couldn't be possible, a nursing mother told me that it is a fact from experience.
Another woman also told me about her neighbour, a nursing mum, who comes back from work and due to the long period she hasn't breastfed the baby, she has to pour cold water on her bosom and let's the accumulated milk run off before breastfeeding her baby.

They claim feeding a baby that milk will cause the baby to vomit, stool and become ill.

Well, I had to do my research, thanks to the internet, we are exposed to a vast wealth of knowledge.

I think these women are wrong.
However, I would want to know what your opinions are.
Spinsters and bachelors, you most likely have no contribution to make so I hereby invite mothers to tell us more.

Illiteracy is a disease and I have promised some mothers I'll be letting them in on my findings.