My 7 year old has just been diagnosed with chickenpox, and her little brother will probably already have caught it from her. We're supposed to spend Christmas with a 60 year old relative who has recently been diagnosed with cancer after a kidney removal. The relative's condition is being monitored but is not undergoing chemotherapy or any other active treatment. They have had chicken pox in the past.
This feels like a stupid question, but is it safe for them to mix on Christmas Day if the chickenpox are still active? I can't find a definitive answer anywhere.