This is from a letter written by King Ludwig II of Bavaria to his old governess, Frau von Leonrod from Hohenschwangau, in January 1871.
"It is really painful to see Otto in such a suffering state which seems to become worse and worse daily. In some respects he is more excitable and nervous then Aunt Alexandra – and that is saying a great deal. He often does not go to bed ofr forty-eight hours; he did not take off his boots for eight week, behaves like a madmen, makes terrible faces, barks like a dog, and at times says the most indecorous things; and then again he is quite normal for a while."Important to note that Otto's uncle was not the first to commit him, but his brother who did truly love him and only did so with great reluctance.
Just before Ludwig II's doomed engagement to Duchess Sophie in Bavaria in 1867, Ludwig II wrote:
"I really have no time to marry, Otto can take care of that."So Ludwig II and the Bavarian court fully expected Otto to marry and have issue.
Maybe somebody here has the Ludwig II almost made a remark in jest about how many cousins get married in royal family, particularly his own. I like infer that Ludwig II was referring to strong possibly that Otto was going to marry on of their cousins. Otto's first cousin, Princess Anna of Modena, was only 7 months younger then Otto and would have been a prime candidate since her mother was very involved in the Bavarian royal family and she arranged the marriage of her husband's niece, Princess Maria Theresia of Modena, to Ludwig III. But Princess Anna of Modena died in infancy.
Another first cousin of Otto,
Princess Therese of Bavaria, was deeply in love with Otto and often visited and wrote to him even after he went totally insane. Considering Princess Therese of Bavaria was extremely smart by any standard, always find it neat that she fell in love with Otto and shows that there must have been something to him beyond "the more insane brother of the Mad King." She lamented Otto's poor treatment by their family.