Why is such treatment being dolled out to citizens on other countries,wasn't this baby seperation thing only reserved for Mexicans and those who crossed form the south.
Officers separate kids from adults committing a crime. i.e. if someone was stealing a car and had a child beside them - the child would be separated after the arrest. In the same way when someone comes to the country illegally they are committing a crime and kids are separated to ensure their safety. It has nothing to do with "being Mexican".
The baby never separated from the mother. Only the father was separated from the two. And reading the other comments, it sounds like this family aren't being entirely truthful with their story.