As a timesaver for you, when you create a Child Bid in an OST Project (an Alternate or a Change Order), all Typical Group Frames and Markers that exist at the time that the Child Bid is added are recreated in that Child Bid.
The Typical Group Frame contains no takeoff at this time because takeoff is not copied/recreated when you add a Child Bid. The idea behind copying over the Typical Groups is that it makes it easier to make adjustments (such as subtracting takeoff using "Negative Takeoff" that affects all existing Typical Group Markers.
For example:
In our Base Bid, we create a Typical Group, draw a Frame, and then place a TG Marker on maybe 10 pages.
We are asked to create an Alternate or Change Order that modifies the takeoff within that existing Typical Group.
When we create our Child Bid, all we need to do is locate the Typical Group's Frame (simply double-click on any Marker to open the Page where the Frame exists, with the Frame in focus), and then we add takeoff and/or add "Negative Takeoff" to make modifications that reflect the desired changes. So, if we need to swap out one Condition for another, we can go back to the Base Bid, copy the takeoff object(s), return to the Child Bid, paste those objects and then set them to "Negative Takeoff". We then draw replacement takeoff to account for the change.
Selecting Takeoff within a Typical Group Frame