Someone, I think did a tutorial on this recently.

You need to stagger your pieces to the left a little bit, so that the triangles on the left and right side peek out a little bit. It looks like the way you have them lined up, you're trying to get a straight edge *before* you stitch them together, when you have to get a straight edge *after* stitching them together.

Look at the diagram just above step 3 and see how the dog ears stick out on the left & right.

I just found this pattern in their book and I wondered if you ever figured out your problem. I thought it was really cute for my granddaughter who is 4 but don't want to try if it is hard to follow. Barb

Unfortunately, I have not worked on it anymore. I still want to finish it, but haven't taken it to my LQS to see if they could help. If you do it, good luck. I love the look of the pattern and was looking forward to having it in my guest room. If I get it figured out, I will add to this post.