Update child records belonging to the modified record

[Dave2]

HI!

I want to be able to trigger an action that changes the values in a child table when there is an update on the parent table records. I thought a workflow would accomplish this, but the only available actions are those related to the same table as the workflow target data. The Workflow help article indicates this is possible but I haven’t found a description of how to do this. Any help or advice?

Thanks