Question about sewing pieces together

For this pattern:
http://cache.lionbrand.com/patterns/60607A.html

is there a way to sew the pieces together without an obvious seam? Would this be a project for mattress stitch? I’ve never used that before.

Would this be a project for mattress stitch?

Yes. Depending on how you work(ed) the sel st it should be very easy. The seaming is also somewhat obscured slightly by the P sts that abut each seam.

cam