Memorial table: family but what about friends?

so i am having a memorial table at my wedding with pictures and a vase with the name engraved on them i am having them at the church entrance so people will see them and then can continue to their seats, i thinking of only have a moment of silence nad maybe a quote or poem read in the their honor.....it my grandmother, and my fiances grandfather and thinking of including a friend of mine from high school any guidelines of adding friend to the memorial table? should i ask his mom if she is okay with it? i sure don't want to offend anybody.....