Toddlers are not scary.
I don’t care if you raise ’em from the dead and give ’em super-strength, there is no way you’re making a toddler a figure to inspire fear. Especially if you put ridiculous looking top hats on them.
In all fairness, Pet Sematary is a halfway decent movie. The acting’s hammy (especially from Dale Midkiff) but Fred Gwynne really sells every line he’s given and Denise Crosby does pretty good too. It’s just when they resurrect Gage and try to make him scary, the movie becomes a pretty funny unintentional comedy.