The pattern suggests working with the yarn held doubled. This produced a very stiff fabric that wasn’t very soft. Also, three hanks makes it an expensive project, at least for the kids hat. Hats are usually 1 hank projects. The ears would naturally add more and that’s understandably, but you can’t even make the hat itself with just one hank.

I made mine with one needle size smaller (Size 15), only a single strand, and I adjusted the gauge accordingly.

The hat knit up very nicely with one hank and retains a nice softness with a second hank for the ears. Worked great. Would make this again.