Yup, for several months there's been and still is a problem with Yahoo email accounts hacked. Those emails usually just contain a link that when clicked on will take you to a webpage that will then infect your pc. Good anti virus security programs on your pc and a Web Shield should stop page opening. I'm using Avast free but any good Web Shield is what you need to prevent inadvertently going to an malware infected page. I also have SpywareBlaster (free program) that blocks most malware from installing. Free program needs manually updating.
Your daughter needs to take the action. First thing is for her to change her password and if possible delete her contacts from Yahoo webmail server if that's possible for her to do. (I obviously don't know if she uses Yahoo as webmail only or if she downloads and sends from her email client program on her pc)
Unfortunately it could also be that now your daughters email is 'out there' other spammers will use it as a spoof 'from' address.
You could set up a code word for your daughter to include in subject header/title of any emails she genuinely sends you. Then you will be able to delete any emails that don't contain the code word.
The action you have taken should mean that you have a clean pc so I would just delete any emails. You could also set up a 'mailing rule' and block them. I have mine set to delete any that contain certain words.