So pair #3! We have here the Ric-Rac Rib pattern from the Little Box of Socks. The yarn is Cascade 220 Quatro. Knit on 3.75mm needles. Fun pattern, but the knitting into the back of the second stitch on the needle and then knit the first stitch as normal really hurt my hands.
Pair #4! We have Baby's First Sock by Ann Budd. Yarn is Sirdar Snuggly 4ply, and knit on 2.5mm needles. Fun, but starting the round with purl stitches hurts my brain. I didn't use the pattern on the sole of the foot because I wanted to stop the purling!