Required Field Validation Group on PeopleEditor control

Very similar to my post on validation of the DateTimeControl, a PeopleEditor (people picker) control I was using was validating on each postback.
I created a required field validator with a ValidationGroup and to get the validator to look at the correct people editor field use the following code.

myRequiredFieldValidator.ControlToValidate = string.Format("{0}$downlevelTextBox", myPeopleEditor.ID);