How many children do you think Pix and Zane would have if they decide to become parents? For some reason I can see them having one or three but also I can see them having like fifteen children and still being excellent, loving parents (the latter would be especially funny because the other ninja would say stuff like "WHY IN THE HECK DID YOU HAVE SO MANY KIDS AND HOW DO YOU MANAGE IT?" and Zane and Pixal would smile at each other and one would say something like "It gives me the deepest joy to have created such a wonderful family with the greatest partner in the world" while the other would kiss them on the cheek.)
I have very specific opinions on this, and really, you can break it up into two pieces.
One kid. One kid which is technologically theirs. They build the one kid and they build her perfect the first time, her name is Circuit, she's like one of my first ever OCs and shes a GEM. I can’t recommend checking her out though, haven’t really done anything with her for a while. *checks blog* 2020?! I haven’t done anything with her since 2020?!?!? wow, okay
HOWEVER- as imortal robot gods they do go on to foster an absolutely unfounded number of children over the years. It starts out as them being the ones running the monestary and training future generations, helping future elemental masters understand their gifts, and those looking for purpose to fight the good fight more effectively- but over time it evolves into anyone who needs help, and they mesurably reduce orphan numbers across ninjago. They get parenting down to a SCIENCE.