I've been reading the original KnitLit: Sweaters and Their Stories...and Other Writing About Knitting and noticing that several of the authors choose to say they are knotting the yarn together with each stitch. I suspect they choose to do that for metaphorical reasons. But it seems to me that the fact that knitting is NOT about making knots can make it a much more powerful metaphor for relationships.
Knitted fabric is one long strand of yarn looped together with no clear boundries or endpoints of the sort that a knot would provide. If you pull at the yarn before you've bound off, all of it unravels, stitch by stitch in order but without end. A knot cuts off one stitch from the next. Knitting binds the yarn together both vertically and horizontally, with what is next to us as well as what came before. To pursue the metaphor, knitting is the connection between us and our loved ones surrounding us but also reminds us that each stitch is an inheritance from previous generations of knitters.