Yes, unless they would not otherwise qualify for an account (e.g., they are underage or have been banned from There). 

However, we strongly recommend that you do not give your account information or password to anyone.  As specified in our Terms of Service (TOS): Behavior Guidelines, the account holder is responsible for all activity on the account. 

"Recognize your own responsibility in having access and allowing others access to your accounts. The person to whom the account is registered is ultimately responsible for any actions from his/her account. Protect your password. There staff will never ask for your password. Do not give your account information out to anyone."

Because you are responsible for all use of your account, you must supervise the use of your account by others.  Your account may be terminated if you let someone use it inappropriately (e.g., violate the Terms of Service).