AJZHEN
I don’t want to be rude but you said you have an editor and if that’s true they are not good at editing like for instance you say “a twin” which is incorrect English it is supposed to be “ twins “ the only time the words a twin would come up would be in regards to one twin out of the two but twins is a plural so when you say “ she is having a twin” it is not correct but “ she is having twins “ is correct in the English language