So, everyone from the Swedish politicians of the day, to some today, assert that Gustaf III's elder son, Gustaf IV, was actually the son of Adolf Fredrik, Count Munck af Fulkila. The politicians even went so far as to assure the Queen at the time, Hedwig of HolsteinGottorp (aka Duchess Lotta), that they would revive those rumors if Gustaf IV's deposition was challenged.
There has often been rumors whispered that a king is actually a bastard - Edward IV, James III, Edward of Lancaster, Prince of Wales, and Lovisa Augusta of Denmark & Norway (Sophie Magdalene's niece) - but was there any truth in these claims?
And if so, was Munck also the father of Gustaf IV's uterine brother, Carl, the Duke of Småland (1782-1783).
What would the results be of a surviving younger duke? Would the rumors die down or at least be regarded as nothing more than malicious gossip?