I highly recommend the pattern. If I have the patience and time, I could even knit one up for the boys (in a boy colour) as it is a unisex cardie. Here's the pattern description:
An easy to knit, seamless & versatile pattern for a unisex jacket/cardigan.
Great for wearing out and impressing people with your knitting whilst keeping kids warm, or for playing around in the backyard.
Complete with a pick ’n’ mix of options - hoods, collar, pockets!
Young Einstein is a seamless pattern. The V-neck makes it perfect for infants as it sits low enough to suit children who dislike wool sitting high around their neck or to accommodate a bib.
Sizing for the pattern ranges from newborn up to 10 years (15-28 inch chest)
It can be knit in either DK (8ply) or worsted weight (10ply) as long as a 20sts gauge is achieved.Information is also provided for substituting yarns of other weights.