Hey! Yup, you are right! I found what caused it and fixed the bug.
Thank you for the report!
funny thing she was my first cursed person I gave her the milk nothing happens and was like o its random if they change that sucks well then just use it on the unique people only then and well then I decided to see what happens if everyone is a cow and well she would not change so figured she had an odd glitch tied to just her.