When adding a new related constituent via the Household tab on the Add an individual form the relationship only appears on the first constituent's relationship tab.
We are currently evaluating this issue for a fix in a future service pack.
Steps to Duplicate
1. In the Constituents functional area, click "Add an individual" 2. Add the first and last name and then go to the Household tab. 3. Add a related individual, and select any relationship type. 4. Go to the first individual's record and check the relationships tab. 5. Notice that the relationship is present. 6. Go to the second constituent's record and check the relationship tab. 7. Notice that there aren't any relationships present.