Exam PL-400 topic 2 question 21 discussion

You are developing a model-driven app. The app uses data from two custom tables. The tables have a parent-child relationship. The parent record form contains a subgrid that displays the child records.
When creating a new child record from the parent form, data must automatically populate in the child record form to reduce data input errors.
You need to implement the solution.
What should you do?