This is an amazing, AU, post-Somalia story, credit to Tempest Erimentha at fanfiction.net WARNING: Ends on a cliffhanger and hasn't been updated for months.
Ziva and Tony have moved back to DC with Tali after Senior had a stroke. All seemed well, until an old friend of Ziva's calls. She shuts herself, and Tali, up greatly. But her new family provides support.