Please be cautious about selecting "Confident".* In the case of Rhys-23 & ap Gruffudd-42, there is not a reliable source given to support that William son of Rhys existed. (An Ancestry link is not a source, much less a reliable one - see the pages [here] for links to Reliable Sources pages; see also [this page] for pre-1500 resources).
Also, I believe the selection of Uncertain for William's parents was intentional (please see [this discussion] about William ap Rhys).
Cheers, Liz
* Once a selection is made, it cannot be "unselected", only changed. For example, many profiles managed by the Magna Carta Project show "Confident" based solely on Richardson's works, although the Project currently requires primary proof before initially selecting "Confident" for a parent/child relationship.