Charlie Sheen: The Kids Were Blindsided By HIV Announcement

Charlie Sheen did not tell 4 of his 5 children that he was announcing to the world he had HIV ... sources connected to Charlie tell TMZ.

Our Charlie sources say although he told 30-year-old Cassandra in advance, he did not tell 11-year-old Sam, 10-year-old Lola, or his 6-year-old twins, Bob and Max.

It's especially problematic for Sam and Lola, who are both in school and have to deal with classmates and others without preparation.

We're told the children are all fine ... free of the virus, but there's a measure of emotional upset that clearly must be dealt with ... and the kids will have to handle it without any preparation.