Yarn for "Einstein Coat"?

Has anybody here made Sally Melville’s “Einstein Coat” using something other than the recommended wool/wool blend yarn? I’d LOVE to try to make my very first garment finally…this looks pretty straightforward–but it would be for my toddler (because it would go fast and I wouldn’t get discouraged!), and I want it to be easily washable.

Have you read through the KAL thread? There might be suggestions for subs in there.

I have the first three of Sally’s books and I really like them. I did begin the Einstein coat for myself but I got bored with it a third of the way done. So I ended up ripping it out. I was using a wool blend.