Why bunnies for Easter? Why eggs for Easter? Why Easter?
The word easter is derived from the ancient germanic goddess Ostara. As a goddess rising from the east, she was responsible for fertileness and the spring. Many different cultural festivities and celebrations were connected to here: i.e. the easter fire and the fire wheels. These events were meant to cast out the winter daemons.
Bunnies get there babies in spring and they often have many of them. So, they are a symbol for fertileness. Btw. primarily rabbits were meant here instead of the hares or bunnies. While hare hide their babies in the boundary ridges and only come at night for a short visit to feed them, rabbits are having their babies in bigger amount around their holes.
Next the eggs. In medieval ages, the famers have had to pay taxes to the landowners. These taxes often / usually have had to be paid in natural produce. Depending on the exact region, the beginning of a new year was on March 1st, spring equinox or April 1st. On that day (new years day), taxes were due. So, the Lenten season also was the time to save food for uses them for paying the due taxes. But, starting from new years day, they were free, to use their products on their own again.
Easter is always on the first Sunday after the first spring full moon. So, we have the Lenten season lasting over the tax date. Eggs were also not allowed during Lenten season. So, the eggs from the Lenten season were marked with different colors to distinguish between old and fresh eggs.