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If this fox is currently sleeping.
During the day, if a thunderstorm is not occurring, foxes attempt to find a space with a sky light level of 14 or less and sleep. Block light has no effect on this. While it sleeps, a fox slowly moves its head up and down. Foxes can also pick up items in their sleep.
A fox will wake up if approached by a player or mob. Foxes do not flee if the player approaches while sneaking until the player gets on an adjacent block.
If the sky light at the fox's position becomes 15 or above, either due to a block above being destroyed or the fox being moved, the fox wakes up. Foxes do not sleep if they are within 12 blocks of an armor stand.