Sole Propr currently and trying to employees? Next step

Currently I have my reselling business and use my schedule C as a sole proprietor. My sister wants to help me and work a few hours a week on my business, so I would want to pay her for her time. Do I need to change from sole proprietor to LLC to add her to the business as an employee? Or if she wants to be co-owner of the company what would be the next step? Small business making 10k in sales a year.