My 4 year old has been obsessed with trains since he was almost 2... It's hard to find train clothing for kids this age, but I found this online and got it a little bit big (size 5) so that it would last him a longer time and he loves it. He says it's very comfortable. We usually buy Carters' pajamas, and I'd say it's similar quality, not as tight as Carters though. There's no tag on the back neck, in case you were wondering.