Help with Child and Adult Xbox Account

An adult account is required in order to set up restrictions for your child's account, ideally you would put gold on the adult account and share that with the child's account that would be added.

For more info on this you can go to https://beta.support.xbox.com/help/Family-Online-Safety/child-accounts/add-family-member-on-xbox-one

This page also covers all alternatives including if there is currently not adult account on the xbox

Hi Hendo,

Thanks for coming to the forums. If the account is still a child it is recommended to keep the adult account assigned to the family until the child account graduates to an adult account. If you are an adult and made a child account in error there is

ways you can prove your age. As on Xbox.com you are unable to change the birthdate at all.

Hope this helps.

Brad

I found this, hope it helps.

Promote a child account to an adult account in Xbox

Xbox LIVE determines whether an account is a child account or an adult account based on the age of the account owner. Account owners who are younger than 18 are given child accounts in the United States. The legal adult age varies by country and region (for
example, the adult age in Korea is 20).

Child accounts are tied to an adult's Microsoft account. The adult account can control Family Settings and restrict some features of Xbox LIVE.

After you reach the age of adulthood (which varies by country and region), you can promote a child account to an adult account. This promotion removes the Family Settings and Xbox LIVE restrictions.

To promote a child account to an adult account

Sign in to Xbox LIVE by using the account that you want to change.

Go to Settings, and then select Account.

Select Promote Child Account.

Note The age of an account owner is calculated by using the date of birth provided when the account was created. This date cannot be changed. If you entered an incorrect date of birth when you created the account, your only option is to create a new account
using the correct date of birth. This option is available only if the date of birth for the account indicates that you have reached the age of adulthood (18 in the United States). The legal adult age varies by country and region.

Follow the on-screen instructions to promote the account.

This should be able to help you :

Promote a child account to an adult account on Xbox 360 :
support.xbox.com/.../promote-child-account

Have a look at this link to help you with promoting your child account to an adult account

support.xbox.com/.../promote-child-account