Yes, you can have separate accounts but they can have the same email for contact.
When you go to the screen where you usually log in for the other account, look toward the bottom and there is a link that says: New to Intuit? Create an account You can click the link in this answer or on the link from the sign-in page. You may make the same email the contact for both accounts, but be sure to save the logins and passwords for yourself. You might get a TurboTax security email from us to alert you that the email was used on two accounts.