To add additional guardians to an existing lead, search for the lead name and navigate to their lead detail page. Next, click the Family tab above the lead snapshot area.
To add a guardian to the existing family, click the +add guardian button on the right-hand side. Then, a new guardian pop-up will appear.
Once you've populated the information related to the new guardian, click save and the information will update on the lead detail page immediately.
Remember, if they're a split family you can also add a new family group to a lead by selecting the add icon.