male kitten adoption question.

Hello there,

One of my friend would like to eventually adopt one of my kittens when they
are ready to go to new homes (8-12 weeks, right?). She already has a male
cat (neutered) that is almost 2 years old, and 2 females (spayed). If she
adopts one of my male kittens, (that she will have neutered too) will she
end up with territorial problems between the males? Will they spray more?
Can other problems occur? Should she adopt a female instead?

Thank you,
Mia, Misha and the bunch