Was that "In loving memory" slide all they did? From what people have said here nothing else has been said either by CBBC Pres or by Newsround so showing that slide with no context is bound to have prompted difficult questions from kids to their parents.
(Lizo Mzimba did a piece on the News Channel insisting that CBBC would handle this really well and explain things sensitively)
I'd have thought they might get an adult cast member to record a short tribute to go out before it - the kind of thing Bill Roach ends up doing when a Corrie cast member dies.
CBBC did a great Newsround special call gone a few years ago with Barney. My guess is CBBC will do something like this at some point. They can't make a documentary in such a sort period of time and due to the subject matter it will take time. Also as the cast member are young they might not feel up to and CBBC don't want to put pressure on them to talk about such a sensitive subject.
That's my guess anyway.
I guess Newsround did not talk about it as they have a small amount of time for a bulletin to explain a lot.