I have been reading the The Martian by Andy Weir, the book that was turned into a film starring Matt Damon. For those not familiar with the story,the main character, Mark Watney, is marooned on Mars when left behind by the rest of the mission crew when they believe he has been killed.
NASA doesn't tell the returning crew that he is alive for fear of causing depression and guilt feelings, messing with their psyches.
When NASA finally establishes contact with Mark Watney via screen typed messages, he is told that the rest of the crew aren't aware he is alive.
Extract from the book:
Tell the crew I'm alive! What the fuck is wrong with you?
. . . please watch your language. Everything you type is being broadcast live all over the world.
Look! A pair of boobs! -> (. Y .)