Automation to add multiple records to a child table.

I have 2 tables that are related. Projects -> Milestones. Each project has scheduled start and completion dates. Depending on the duration of the project (Completion-Start) I have x number of weekly milestones , i.e. ToWeeks(Duration). How do I create an automation that adds a record in the project child table that represents each of the X number of milestones including the start date for each of the milestones. I would like to do this addition of project milestones on a schedule for all projects and by a trigger in a Project.

child table result after the automation runs should look like this:

Project name    Milestone # Start Date
ABC                    ​1                  Project Start Date
ABC                    2                  Project Start Date +1 week
ABC                    3                  Project Start Date +2 weeks
ABC                    4                  Project Start Date + 3 weeks
.
.
.
ABC                   X                   Project Start Date + X weeks

The duration of weeks changes so I am trying to get a history of information in the child table.

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George Bramhall
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