This is perhaps a dumb question, but since I have to order my fabric online I need to ask. I am sewing Art Museum ensembles for my son and the other ring bearer in my sister-in-law's August wedding. She wants the vests in gray gingham with khaki pants. I think I will also do the backs of the vests in the same khaki. I feel like the fabric should be the same, but on the other hand, it seems like the pants should be more of a bottom-weight fabric like a twill, which would be too heavy for the vest. What do you think? The boys will be about 18 months and 2 at the time of the wedding, if that matters.