Not getting notifications of messages from only one person.
My wife’s iPhone allows her to get notifications and vibrations when she gets a text message from everyone… except one person. She gets the text messages, when she looks later they are always there, but no text tone or vibration. So she gets a text but does not know it and therefore does not answer promptly. This only happens with one out of all of her contacts, her sister in law. Her sister in law also has an iPhone. I have searched the web and tried checking things in contacts and in settings and every toggle and option is set the same as the rest of her contacts. Any help or advice would be most appreciated.
iPhone 6s