and found that I needed to combine everyone into a single unit study. However, I ended up doing several weeks of "Bigger" 7 weeks? (guessing) Next year, I am planning on using Bigger with everyone. Would you start all over again or just start the younger boys and do light review with the child who already did the lessons. It will be 1 1/2 years since Colton did Bigger by the time we start it. What are your thoughts? 
), but if it were me, I would just start at the beginning with everyone. If it has been more than a year since your one son had it, he might remember a little bit of it, but there is certainly no harm in having him go through it again to get into the swing of things.
you'll know that he remembers it clearly and then maybe he can skip a little at the beginning if needed? The other thing you can do is say, "I know, honey, that you did this before, so I'm counting on you to help me teach these first few lessons to your little brothers. Do you want to act out this bible verse for us? Could you help them with their art project?" 