When the gypsy, Madame Marova, is complementing Little Joe, he mentions he is the youngest of all, Hoss being the biggest. Little Joe did not mention his oldest brother, Adam Cartwright; there was no need as it did not relate to Madame Marova's question. Besides, Adam (Pernell Roberts) was "long gone."
On Madame Marova's wagon, what should have read "SEES" (as in "SEES ALL") was misspelled as "SEE'S." There should not be an apostrophe there. BTW, it is unclear as to how so many people on the crew, to include the actors, missed such a blatant misspelling. Thankfully, the other two "ALLS" were properly spelled ("KNOWS" and "TELLS"). BTW, it is believed that the misspelling was on both sides of Madame Marova's wagon. (Consistent, yes, but.)
During the opening sequence, Hoss stops to help a damsel in distress in the form of beautiful Gypsy Fortune Teller. Maybe Dan Blocker was stymied by Sha Sha Gabor's presence and grace, however at time stamp 0:25 Dan Blocker says "It's alright ma'am be happy to help you do it. [fix wagon wheel] My name's Horse Cartwright, ma'am." Instead of introducing himself as 'Hoss'.