The wildly successful writer, director, actor and TV producer just filed for a restraining order against Colette Barris -- his own sibling, who teaches professionally and also writes books -- because of fears Kenya has that she's going to harm his kids ... in one way or another.

In the docs, obtained by TMZ, Kenya documents years of alleged incidents in which he claims she piggybacked on his name and their familial relationship to hook herself up with opportunities in Hollywood. But, after failed attempts to get her own projects off the ground -- either because meetings went nowhere, or because Kenya refused to help her -- he claims he now worries that Colette will take out her anger against him on his six children.

Due to that, he's now asking a judge to enforce a court-ordered shield of protection -- even if temporarily -- so she has to stay away from him and his family and cease communication.

Kenya says he's had a rocky relationship with his sis for years, all because he claims she insists on cashing in on the family name and using him for her own prospects ... not to mention allegedly demanding he take care of her and their extended fam with cash.

Kenya describes several alleged episodes in which he says Colette has procured meetings with big shot studio executives to pitch TV show ideas of her own ... all under what Kenya calls false pretenses, using his name and fake support to cozy up and secure face time. In some instances, Kenya says things actually got rolling for her ... all because some execs felt pressure to help Colette due to pending projects with him.

There's also this ... Kenya alleges Colette recently sent him a legal demand letter, saying he MUST fund a movie project of hers in the amount of $4 million (based on a novel of hers). He also claims that she's told him if he doesn't do what she says ... she'd go public.