All of the CAT thresholds (except the small gift exemption) are per recipient in the recipient's lifetime.
So the first €32,500 received cumulatively from everyone in Group B is exempt. ( Uncle, child, niece etc.)
So if Uncle Bob gifts your €40,000 and Aunt Dahlia subsequently leaves you €20,000 in her will, the entire €20,000 is subject to CAT.
Likewise if you mum gifts you €400k, and your dad subsequently leaves you €100,000 in his will , the full €100,000 is subject to CAT.