Some time back we bought an apricot tree that had been grafted. For whatever reason, the apricot tree took off and suddenly died. At the base green sprouts appeared and began to grow rapidly. We were actually hoping they were from the apricot, but based on the leaves, we figured it wasn't the case.
The following year, as it had fully filled its pot, we planted it, and, to our surprise, it bloomed beautifully and began to bring fruit. A few months down the road, the fruits are now ripening into what may be small prunes.
We're impatiently waiting to taste them.