My memory has fallen into a hole, but which Festivals have something like the Sylesti Sculpting where you need to feed your new child a large amount of supplies.

I vaguely remember Summer/Spring Fest has a garden and Winter has snowmen; but I feel like there's more (or their specific names)

I am relatively new and thus have only seen one fall/winter fest and don't remember much of the two spring fests, but as far as I know, all the festivals have the sculpting (though the ycall them different), and with at least two, you get various bonuses on your pets if you keep on top of giving them agents (or have other players do it).

The winter fest I went through didn't have snowmen (that was one of the things removed), but still had sculpting, though I can't remember exactly what it was like, Spring fest had a garden where you could put water onto a 'flower' to make it more likely to encounter a specific type of pet in the zone as well as flower fairies, as well as having a sculpting area where you could use agents.

Fall fest also has an area like that, but Idon't remember the specifics for it.

Sorry if this didn't help, but I am not exactly sure what you mean, unless it is the ones where your sculptures don't need agents to progress like Summer fest does, but making sure they are constantly taken care of will give various bonuses to the resulting pet.

As Jemadar said, theres some kind of themed pet creation activity in every festival. This one is Sand Sculpting, obviously, the Fall one is Brewing, the Spring one is Plant/Flower growing, and the Winter one is Ice Sculpting. In terms of which ones require near-constant attendance (and thus lots of supplies) due to no auto-progression, its this one and the Plant/Flower growing. The Fall and Winter ones do have that component, so the only effects if you have a hard time keeping up with maintaining them is lower stats, fewer bonuses, and more time for them to finish.

Actually, it's only Summer that doesn't have auto-progression!

Fall Brewing, Winter Ice Sculpting, and Spring Gardening all progress slowly on their own, but have bonuses for you keeping them cared for (with two total bonuses, in the form of bonus stats and an extra carried trait for regular and fabled, and two stat bonuses for majestics)
(they also progress faster the more you keep up with caring for them)

(it's possible Summer will have some sort of auto-progress implemented for next year, since now summer is the only one that doesn't auto-progress. I think it was sort of intended that it would be added, but with all the other things Krin is currently working on it was put aside for the moment)