It’s not common that a Jedi will be elevated to the role of Master without first being a Knight for some time, but there is one in recorded history that’s done so, and she’s even a part of the canon since she’s been seen in one of the prequels. Yaddle is one of the only, possibly THE only, individual that has ever gone from being a padawan learner to a Jedi Master without the benefit of having been knighted, and there’s a reason for this. When she was on a distant world with her master the story goes that she and her master went up against a local warlord. Unfortunately, the forces sent against them were far too many and her master was a bit too arrogant in his manner as he attempted to rally to take on the entire army. That didn’t end well as her master was killed and Yaddle was tortured and then imprisoned in a pit for two centuries. To curry favor with the warlord the people did their best to mock and belittle her, but some kept her alive by feeding her throughout the years, and eventually, she became a legend that the people lived with since like Yoda she is very long-lived thanks to the nature of their species.
Eventually, Yaddle did manage to escape after the village she was entombed beneath was assaulted by a descendant of the warlord that imprisoned her, and instead of taking her revenge on people who weren’t even born when she’d made a prisoner she helped them against the current warlord. Over the course of two centuries, she held onto her Jedi training and improved her skills little by little, keeping herself sane and her senses attuned and sharpened as she went over the many lessons that she’d been given before her master’s death. When thinking that some people can’t show such discipline for more than a year, the idea of spending 200 years in an underground cave with only enough food to survive and the abilities that one was taught as a student, it’s hard to think that anyone would come of such a situation with their mind intact, let alone their body. But Yaddle somehow managed to hold on to who she was and kept up with her training even as the people above sought to keep her alive, at one point offering food out of tradition more than anything else.
It goes without saying that Yoda was against this since there was no proof other than Yaddle’s word and her abilities that what happened really did happen but considering that she wasn’t a liar and was incredibly skilled it was easy enough for the council to believe her. The only doubt that would eventually come would be born from the fact that the Jedi Council had no idea that Palpatine was a dark lord of the Sith, but thankfully that had no bearing on Yaddle’s story. Instead, she was accepted as a master, having never been knighted and with the knowledge that she’d been out of circulation for two centuries. Unfortunately, when it came to live-action, Yaddle would only ever be seen as one of the sitting masters that never spoke and was only prominent in the graphic novels and eventually in the EU series where she became one with the Force eventually. Her story has been largely bound up in the comics and not much else, which is kind of sad really since she was a great a Jedi, maybe not on par with Yoda but definitely powerful and quite skilled. With their people’s obvious affinity for the Force, it’s likely that Yaddle and Yoda are two of the more powerful Jedi that have ever existed. This kind of makes a person think that The Child might not only have a name that starts with Y but is also going to be insanely powerful if his ability is harnessed for good at one point.
Her demise has been changed to fit with the current canon and there’s now a question as to whether The Child is bound to be associated with her as well, meaning that she could have a connection of sorts with The Mandalorian. But likely as not we won’t be seeing her again unless someone is going to pull a quick and somehow successful trick that will see her re-enter the Star Wars franchise somehow decades after she was supposedly killed. Again, that doesn’t sound likely since her body was laid to rest and her place on the Jedi Council was taken. But it might be worth it if she gets a mention at some point since she’s one of the more impressive Jedi that hasn’t really been recognized as much. Plus, it’s always nice to see another member of a species that people don’t know that much about.