If you have Admin access for a child's profile, you can manage others' access.
​
1. Tap on the Me tab and then My Family:
​

2. Tap on your child's name:
​

3. Tap 'Add admin' if you want to update your partner's access, from Story to Admin access (or invite a new Admin):
​

4. You'll get a pop-up asking you to confirm your decision:
​