Set default date for date picker

For date fields I can set a default date through field('..').def(). However, I prefer to not have the date fields pre-populated, but only have the date picker be positioned on a default value.

For instance, if I have two dates, the admission date and discharge date, I would like the discharge date's date picker to be positioned on the admission date, but I do not want the discharge date to be pre-populated with the admission date.

Can this be done?

Thank you for your feedback.