Need help finding an old anime

Hey guys

I have remembered a scene from an old anime (i mean old). It was at a water park and these 3 kids when down a slide and disappeared if I remember correctly. Then they were floating in some other dimension and there was this bad guy waiting for them. Then the 3 kids did something with the watches they had around their wrist. It cut to an attic with three dolls that then shot up or teleported or something and went to save the 3 kids and they were fully grown adults and then there was a fight.