This has bothered me for all of season 1 and now in season 2.
We all know that Mako and Bolin are brothers, we all know that Mako is a fire bender and Bolin is an earthbender. what I want to know is HOW?
The only explanation I can find is that a Firebender married an earthbender and had Mako and Bolin and because only the Avatar can bend more than one element, Mako got the bending from one parent and Bolin got the bending from the other parent.
That isn’t the part that bothers me. It’s the fact that we know NOTHING about Mako and Boiln’s parents. Think about it. We know more about freeking Zuko’s mom and Katara’s mom put togther then we do Mako and Bolin’s mom and dad.
I believe it’s been confirmed that their mother was fire nation descent and their father earth kingdom. Although, I can’t recall whether both of them were benders. Not like it would matter because non-benders are capable of having bending children (Kya and Hakoda=Katara), as well as the other way around (Aang and Katara=Bumi). Very little is known about them besides what we know so far, but I’m hoping that we get some flashbacks (anything) in the further books.
It would pretty much have to be something like what millionvoicesunwritten said. Aang (air) and Katara (water) had 3 children: Bumi (non-), Kya (water), and Tenzin (air). For siblings to have different bending abilities, they jus need to have parents with different abilities. Plus, Mako and Bolin grew up in Republic City, which is unaffiliated with any particular tribe, so it is quite plausible that their parents met and married there.
And now I’m interested in Avatar and bending genetics. If Katara and Aang had had more children, could some of them been earth or fire benders since Aang was the Avatar and could bend all four elements? Is Avatar-ness a purely spiritual thing or is there a physical/genetic modification as well?
Also, since Tenzin is an air bender and all his children (so far) are air benders, does that mean his bend-capable children can only be air benders? Or since his mother was a water bender, could he have a water bending child/grandchild? Do Bumi and Kya have children? If they do, what are their bending abilities, if any?
GAAAAAAAAAAAAHHHH! So many questions!!!!