They have a separate area for kids less than 3 yrs. That area is not very crowded. Still you can try weekdays in the afternoons or weekends in the morning.
Weekdays in general are less busy and the best time would be around noon when everyone goes for lunch.
Weekdays when most kids are in school are less crowded. Avoid weeks when kids have school breaks (winter break, mid-winter break, spring break and fall break, or Holidays).
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