Future Father In Law wants to attend Bridal Shower

I have been so excited about my bridal shower. It is the one wedding thing that I knew I did not have to handle, plan or worry about...until now. Last night my future husband came home and said he had spoken to his mom and she and her husband want to know if her husband, my future father-in-law, can come to my bridal shower. Isn’t it common knowledge that the person whose name is on the invitation is the only person invited? Also. I think she should have contacted the people who are throwing the shower (my mom and sister) and asked them as not to burden my future husband and myself with the worry about saying no. It seems like she knew the answer would be no if she asked my mom and sister, and so she put it upon her son to ask me in hopes of a better answer. Her asking my future husband and I this puts ys in an awful spot. My future husband said that he and his dad will be hanging out together during the shower which is great for them but bad for me in this case because I was really hoping that my future husband could come and make a cameo appearance at the final half hour of the shower. I envisioned him coming in getting to say hello, seeing the beautiful presents we received and him sitting down having a plate of food and then helping us pack the car up. But now I have to worry about his father coming along with him and grilling me the way he always does about work and things non-wedding related. If his father had been pleasant in the past and not grilled me about sensitive topics all the time I might consider him coming with my future husband at the end of the shower. But since this is not the case I really do not want him there. This is not the first time my future in laws have created such problems for my future husband and I. It is sad, but now I feel like I have to be on the defense around them since they so often put their own needs’ and feelings before ours. . Has anyone had this type of request from their future in laws? How can their son and I maintain healthy boundaries with them?