A person can only be in one Microsoft family group at a time. To move from the current (empty) family group into the husband’s family group, the account must first leave or be removed from the current group, then be invited to and join the new one.

From the provided information, the supported path is:

1. Confirm that the account is indeed in a family group
   • Go to the Family Safety dashboard at family.microsoft.com and sign in with the account that owns the “empty” group.
   • If this account is shown as a Family organizer, it controls that group.
2. Remove all members from the “wrong” family group
   • Still signed in as the organizer of the empty group, remove any other members (if any) from that group. Members can only be in one family group, so they must be removed before they can join another.
3. Leave or delete the empty family group
   • A member must leave or be removed from a family group before joining another. The documentation states that “Members can only be part of one family group. A member will need to leave the current family group to join a new one.”
   • Use the “leave/remove from family group” option described in the help article referenced below to exit that group entirely. Once the account is no longer in any family group, it can join the husband’s group.
4. Join the husband’s family group
   • The husband, as a Family organizer, signs in at family.microsoft.com.
   • He selects Add a family member.
   • He enters the email address for the account that just left the old group, chooses the role (Member or Organizer), and sends the invite.
   • Open the invitation email, select the link, sign in, and accept to join that family group.
5. Add the child to the correct family group
   • Once both parents are in the same family group, the organizer can add the child’s account using Add a family member, entering the child’s email or phone number and sending an invite.
   • If the child is already in a different family group, that child account must first leave or be removed from that older group before joining the new one.

If the UI still does not show any option to leave the current group even though the account is a member, the documented workaround in similar cases is to temporarily join a trusted person’s family group as a member, have that organizer adjust any needed settings, then leave that family afterward. This confirms that leaving and rejoining groups is supported once the account is no longer locked into the original group.

References:

• Add people to your family group
• Getting started with Microsoft Family Safety
• Share your Microsoft 365 Family or Premium subscription
• Manage Microsoft 365 Family subscription sharing
• Set up Microsoft Family Safety
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