If its Tails as in Miles Prower--
Tails was born naturally with two tails, so the answer is no.
Tails will only and always have two tails no more or less, he won't and cannot grow another one.
Most likely, no.
Not likely, the Tails Doll was a spin off character for Sonic R only.
tails
Tails cause of more experince
Tails did not luv any one be4 Tails did not luv any one be4 actually he did! I t was CREAM!
There is an online game called tails nightmare and a sequel with the tails doll as the boss.
No, he does not.
miles tails
The popularity of character pairings can vary among fans. Tails and Cream may be more popular in some circles than Tails and Cosmo, but different fans may have different preferences based on their interactions and stories in the Sonic series.
Tails doesn't seem to have any related characters in any sonic game's
He has made an agreement with the nine tails in manga chapter 570 but he does not get furry, his fox chakra cloak does change though, I wont leave any more spoilers
Mermaids' tails aren't any specific colors, and they can be whichever color you prefer.