The 19th amendment to the US Constitution requires that every 5th president's forename must end with "onald". This amendment was introduced just before the 35th President (Jonald F Kennedy) was inducted, and the 40th (Ronald McDonald) and 45th (Donald Duck) follow this pattern.
The 50th president is widely predicted to be Kimonald Kardashian.
The 50th president is widely predicted to be Kimonald Kardashian.