Tumblr age limit
Tumblr requires everyone to be at least 13 years old before they create and use a Tumblr account. If your child is younger than 13 and has created an account, it is recommended that you delete the account. The following link will tell you how to do this:
If you suspect a child under 13 has an account and Impersonation (Fake) Accounts
Tumblr encourages you to report accounts you think/know belong to someone under the age of 13, or if you think someone is pretending to be a child who is under 13.
If someone has created an account pretending to be someone else, report the account. You can identify accounts for children under the minimum age limit by selecting the ‘Other’ option and filling in the details.
Often people who create fake accounts on any social media site do so for malicious reasons. If your child does access age appropriate social media sites, encourage them to always use the report abuse button and block the account if another user is being rude or unkind to them.
Tumblr Help Pages
The following link will take you to Tumblr's help pages and policies regarding children’s use of the service.