If its truly all one plant, not two separate plants stuck together by accident in the same pot, this would be known as a "bud sport" -- not rare at all, this is the way many, many varieties of plants have been discovered. In particular, plants that are color variations of other varieties, such as 'Red Anjou' pear, are often bud sports. Per wikipedia, there are 42 patented bud sport varieties of Red Delicious apple alone.

Thank you for your reply. It must be a bud sport as it is all one plant, everything comes off of one stem.