Bridal Shower Guests

My MOH/sister is throwing a bridal shower for me. Someone that I do not have on the wedding list responded that she couldn`t make the shower. My sister now can`t remember if she invited her. Two other sisters got married in the last year so I am not sure if my sister accidentally invited her thinking she was on the list or if this guest just assumed she was invited. She is a 2nd cousin but close in age to some of my younger sisters so they invited her to their wedding but I don`t feel close to her and didn`t want to start selectively inviting 2nd cousins and hurt other`s feelings. Is it ok for me to leave her off the wedding invite list still? My concern is that my sister really sent her an invitation so she will be confused about not going to the wedding.