Camellia : tea-born borrowers ! (Tea BB's)
They are usually born to be around 3~4 inches tall and are not any heavier than a teacup. As they grow older and gain trust from a human, they grow taller (up to 20 inches).
Not immortal-- but can outlast a human or two. It is also possible that they never grow, if they have no human relationships. They can die of any other natural cause.
(How are they born ?) Naked as a babe at birth, it is possible to find their diet-- sugar-- because they have birthmarks. It is possible to have one up to three marks. Usually a shade darker than the skin and shaped like the sugar they should eat (example: