noun
reunification
ree-yoo-nih-fih-KAY-shun/ˌriːˌjuːnɪfɪˈkeɪʃn/
The process of bringing separated parts together again.
The two halves of the toy bridge undergo reunification.

Etymology
Unification makes a unified whole; re- adds the idea of doing so again. In this sense, joining the separated parts restores an earlier unity.
In context
Reconnecting with family is so difficult. Reunification with their kids, I always advocate for family counseling
More examples
- Families celebrated their reunification after years apart.
- Reunification brought the divided organization under one board.
- Negotiations focused on peaceful reunification.
Forms
reunification
reunify verb — join previously united parts again
Similar words
- unification
- Unification joins things; reunification joins things that were previously united.
- reconciliation
- Reconciliation repairs relations; reunification restores a joined entity or group.