This is only if the speaker is male, right?
Yes. Shiyáázh for female speakers.
How do you say "son"? (Not my son)
Like all other kinship terms, use shi- for my, ni- for your (sg), bi- for his/her/its, and a- for someoneʼs.
Ayeʼ / amá / atsilí: someoneʼs son / mother / younger brother
Shiyeʼ / shimá / shitsilí: my...
Wrong tone: shiyeʼ