Shaq involves the kids in UGLY divorce...NOT COOL!

Shaquille O'Neal ordered his six-year-old son to deliver a death threat to his estranged wife's boyfriend, according to documents obtained by TMZ.

Shaunie O'Neal, who is going through a bitter divorce with the basketball star, claims Shaq ordered their son to tell her boyfriend that Shaq "is going to kill him," and even screamed at the boy, demanding -- "Say it now! My daddy is going to kill you!"