So I am having a destination wedding on a beach & I have an older sister whom will be my maid of honor & my fiance has a younger brother that will be his best man. My fiance also has 2 children, a boy, & a girl, who are teenagers that will also be in our wedding. I also have a younger brother & would like to incorporate him in the wedding as well. What kind of duties can I have him be part of or do? Could he be a groomsmen even though there is no bridesmaid for him to walk down the aisle with? What other things can he do? We will only have about 25 to 30 guests.