In a Household Membership, reservation visibility is not currently shared across family accounts. Each account only sees the reservations made under that specific account.
If one family member books a property, the primary account holder and the other family members do not see that booking in their portal.
Shared visibility. Shared reservation visibility across a family group is not part of Household Membership today. If you need it, contact support and describe how your members book, so the request can be reviewed.