I forgot the
Parent Mode passphrase.

Parent passphrase required prompt with Forgot the passphrase link
01

On the child's phone, tap Forgot the passphrase? then Ask a parent to approve.

The Account screen on the parent's phone with Parent Mode requests and Review requests
02

On your phone, Account shows the request. Approve it; the 24-hour wait starts.

Save your backup recovery code screen
03

No second phone? Enter the backup code from setup instead. Same wait.

Get Eclipsis. Free on the App Store. The slowdown and Parent Mode are Eclipsis Pro.

Get the iPhone app

Questions

Why a 24-hour wait?
So ten minutes alone with an unlocked parent phone cannot undo the setup. The wait shows on the child's phone, and typing the real passphrase cancels it.
What happens after the wait?
Eclipsis asks for a new passphrase and issues a new backup code. The old ones stop working.
I set it up without an account.
Then only the backup code works. Sign in on the child's phone later and the approval route becomes available for next time.

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