Pets is seemingly clocking at around half an acre. It could easily clock in, as just the showbuilding is at around .56 Acres, and if you include the queue..can go to potentially .1 Acre more.
That said, I would imagine Kidzone would be more likely, more to where Curious George or Barney is at this point, if it does go forward.
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If anything, I could see them potentially open the area (not exactly the attraction) around by the end of the year; just to get more footspace for the Upper Lot.