Yes there are 4 large tables, get there early!
We had our 2 year old daughters bday here last year. Two other families did also. Each party took a table each. The week prior to that 3 families were having their bday parties also. Someone even had a face painting booth setup. Dont call Willow Fork for permission, they wont care. Just do it, get their early to setup. Have fun.
Yes you can have , better have the permission.
I don't see why not... Of course it is a public park so anything too disruptive would be discouraged. But a regular birthday party should be fine.
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