As Witzend said, some patterns for babies are old fashioned and fussy, which is why they may not be worn. I’ve rarely seen a modern baby in a matinee jacket, but still see them for sale at craft fairs.
Cardigans and jumpers in the bright, multicoloured, synthetic yarns that are widely available now are popular with my grandchildren, but probably only up to 2 or 3 years old. The Fairisle effect ones are fun to knit as you see the pattern develop without any effort.
Not sure if GD is into unicorns yet but janea’s one looks great. Must look out for patterns like that.