Issue with paragraph breaks in email templates

I've designed and coded an email template for my client. However, they're having issues with paragraph breaks being removed when they copy and paste their text into the visual editor. If they add their text into the HTML editor and add their breaks manually, the issue is resolved. However, they feel this is a clunky solution.

Is there something that can be added into the template itself to preserve these paragraph breaks within the visual editor? 

I'd appreciate any assitance or advice on this topic. Thanks!