AITA for refusing the +1 of my sister at my wedding?

Basically my sister asked me if she can bring her new boyfriend to our wedding.

We have seen this person about 2 times and dont know him very well. Furthermore she never presented him to us as her boyfriend.

Its a pretty fresh relationship she has.

She asked 1week ago if she could bring him(2weeks before the wedding).

Our wedding is next week.

Am I / Are we the assholes for refusing it?