User blog comment:EF5tornado/Guys please listen/@comment-1038387-20150929200206

To elaborate on Puffle's reference to COPPA:

The Children's Online Privacy Protection Act (COPPA) forbids US-based companies from knowingly storing the personal information of people under the age of 13 (without a parent's explicit, legal, written, permission in advance). Therefore, Wikia has set in its Terms of Use a clause which says you have to be 13, and you acknowledge that you are. Once they know you're not, you broke the Terms of Use, and they have to deactivate your account. Because they then violate the law.

This is a law that affects Wikia, Inc.; not its users or wikis. The proper course of action is not blocking, but reporting to Special:Contact/general - which will lead to the account being disabled. However, admins (or any user) will not be held accountable if they don't report underage users. It's up to Wikia to enforce their Terms of Use. Wikia does not shut down wikis (solely) for having users that are under 13, nor does it block people for not reporting people.

This law is in place to protect younger children from handing over their private information to websites. Wikia has to follow it; for complaints, write to your local representative/embassy.