Vacation Bible School

I love the week after school gets out here, my nephew comes to stay with us and attends the local Vacation Bible a School! I just love having him here and so does his cousins. Thad and him play for hours and he just dotes over Jocelyn! 

 

The only problem I have is when we get to the end of this ally the church is a block away, Thad sees it and realizes that Gavin is going and he is not and he will throw a big fit! I talk to him and tell him Gavin will be back in the afternoon but no use and since he's still not taking its a one way communication. We get home and he'll sit in the wagon and cry or pout for about 5 minutes which I ignore and then everything is over. How do I prevent the tantrums in the first place?!