CellFamilies contains the data on the Families which are the third level of the Tracking Hierarchy. They are comprised of multiple cell tracks which are associated together by mitosis.
### Field Values
| Field | Description |
| -------- |--------- |
|RootTrackID | ID of the first parent track associated with this family |
|tracks | List of tracks that associated with this family |
|startTime |Time value of the first hull in the family |
|endTime |Time value of the last hull in the family |
|bLocked |boolean indicating if the family has been designated as [Locked][1] by the user|
|bFrozen | boolean indicating if the family has been designated as [Frozen][3] by the user|