I'm currently working on my second project with Plymouth Encore--first made a baby bunting, now a baby blanket. It was recommended by my LYS as an excellent yarn for babies & children due to its softness, warmth from the wool content yet it's easy care. The color selection is wonderful so it's sometimes hard to decide which to choose.
Cascade 220 also has a nice color selection. I just bought some to make the Fuzzy Feet felted slippers, but have not worked with it yet. It seems like it would be a nice yarn for an adult sweater, but I probably wouldn't use it for a child because of the care issues.
Whatever you decide, I hope you post a photo.
Socks, Mountain Colors Bearfoot in "Sweet Pea" colorway.