Making the sand box way BIGGER

So we had the sand box next to the garden boxes. Because are backyard has tons of trees are garden boxes havent done so great. So we decided to make the sand box 4 times bigger. My great husband and father n law finished it in no time flat, even with a broken arm. The first picture is how it was before and then you can see the in between sand box and just imagine 2 more truck loads of sand and it boxed in thats what it looks like.