Little Severian and the Thing in the Jar

<newbie alert> I¹ve been lurking on this list for a while, and I¹ve finally decided to start posting (I¹ve had trouble with finding a computer to subscribe with - it¹s a long story) Anyway, I recently reread BotNS. Many of the things that might have confused me have been discussed on this list, leaving me even more confused. :-) However, there are two major points I haven¹t seen discussed. The first is the thematic point of the whole sequence in Sword with Little Severian. I can see how it suggests Severian has a sister, lets Severian¹s development of a conscience be shown, and carries forward a few plot points with Agia and Alzabos. But Little Severian is around for a long time to be just a plot function, and I don¹t quite get it. The second is the scene in Citadel with the homunculus. I have no idea what this is about, other than possibly a reference to the works of Samuel Beckett. The Encyclopaedia of Science Fiction suggests that this is Severian¹s sibling, but Merryn seems far more likely from previous discussions here. I really hope I¹m not asking something everyone understands so well they¹ve never bothered mentioning... <g>