By Emma Mackenzie The King is set to attend the annual Windsor church service to mark Easter Sunday – but for the most part, he isn’t able to conduct many of his planned royal engagements as he undergoes treatment for cancer. The reason for this is that his medical team has advised whilst he is receiving treatment he avoids “public-facing duties” for the time being. However, this inability to appear in public has left the monarch “frustrated” and an expert has claimed that there is one reason in particular why King Charles is still determined to keep working behind closed doors on other busine…