So, I have one niece and one nephew (6 and 1 1/2) that mean the world to me. And I definitely want them in my wedding. (My niece is already asking to be my flower girl

) BUT, my husband-to-be has THIRTEEN nieces/nephews. Plus two very young brother and sister. All of these children are under the age of 12. I don't want to leave anyone out, but I don't want to have a plethora of flower girls and ring bearers...Does anyone have any sugggestions as to how I address this? Any other spots they could fill that I haven't thought of? Thanks in advance!