Options: Modify field in ALL children records, based on Parent record field

I am trying to determine which would be the most effective and efficient way to accomplish a goal.

When a certain field is completed in the Parent record, I need specific fields in ALL related child records to be completed.

Example: When I click the "Job Approved" button, it fills in the "Job Approved Date/Time" field with a date/time stamp of when the button was clicked. It also fills in the "Job Approved By" text field with the First & Last name of the User who clicked the button.

When that happens, I need the "Assignment Approved Date/Time" field and "Assignment Approved By" text field to be filled in by with the same date/time & User name as the corresponding fields from the Parent Record (Job).

I was thinking of two possible scenarios:

1. The "Job Approved" button does all the work (if possible).
   • This would require that it go to each related child record and update the corresponding fields.
     • The number of related child records can vary.
     • Not even sure if this is possible
2. Use automation to detect once the "Job Approved Date/Time" field is not blank.
   • It then updates all corresponding child records with the pertinent information in the corresponding fields.
   • I can detect the change and make changes to a single child record, but am having difficulty in doing it to ALL child records.

Any insight, thought, recommendations, ideas, suggestions, etc., to push me in the right direction is very much appreciated.

I honestly feel like the Button would be the best because it would be a one-done kind of a thing. Press a button, done.
Whereas with automations, I would be concerned that it wouldn't catch or trigger and it would cause issues.

Thoughts?

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Andrew
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