Regarding kids picking stuff up:
You should have to direct a kid to pick up any new item (including mushrooms with different food values). That way you keep the challenge in finding collections.
With very young children, aged 2 to 4, they should be instructed each time to pick stuff up. You have to do that with kids that age in real life, right?
When the child turns 5, they can begin to pick up items near them on their own. Anything that's not new, that is.
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