Here's my theory about children, right: grown-ups make 'em as an excuse. Adults want to play with and wear and visit all the cool stuff aimed at children but feel embarrassed about that, so they squirt out a sprog and "Oh, little Amelia would adore the Hove Park Railway, we must go!" No mate, I've ridden that miniature steam train, and most children looked bored while all the adults beamed and screamed and cackled. It even has a tiny shovel to feed tiny coals into the tiny boiler! Amazing.
It's Spring Again [official site] is cheaper than a baby and certainly cleaner. And its Collector's Edition comes with a 20-minute puppet show.
Supposedly it's an educational game "for children ages two and up" but I don't think children would fully appreciate how wonderful it is when e.g. a rainbow saunters past on tippy-toes. No, this lesson in what the seasons are and what they do to the Earth and to trees and flowers and animals and floweranimals is clearly aimed at non-parents in their thirties looking to brush up on their natural sciences.
It's Spring Again is £0.71 on Steam right now for Windows, Mac, and Linux. But! For £1.79, you can get the Collector's Edition which includes the 20-minute puppet show the game is based on. I would recommend paying the extra quid, even if only for when they put mittens on the Earth.
It has four achievements and I've unlocked ALL OF THEM. 100-percented that bad boy.