Bruce Jenner -- Jenner Sources Call BS ... Kris Jenner Knew for Years

The Kardashians are lying when they say they were blindsided by news that Bruce Jenner was becoming a woman, and in Kris' case she's known for years ... sources directly connected to the Jenner family tell TMZ.

We're told Jenner's sons are finding it hard to stomach reports that Kris had no idea Bruce was becoming a woman. That's exactly what Kardashian sources told TMZ, that Kris was in the dark.

But that has infuriated members of Bruce's family, who say Kris has known since they got married that Bruce "had issues with his sexual identity." And they say his desire to transition surfaced years ago.

Our Jenner sources say Kris wanted it under wraps because it would "hurt the brand." So for the last few years they say she was ironfisted about keeping it all private.

We're also told the Jenner boys are upset with Kim -- although they will deny it publicly -- because they are convinced she knew exactly what she was doing when she talked about Bruce's journey and she jacked Bruce's moment.