This blanket was made by my mom using the crossed double crochet stitch. You can see a detailed tutorial for this stitch here.
The blanket has a rectangular shape, and my mom crocheted along the longer side. She made a few stripes of different color as she was somewhat short on the white yarn. You can make this blanket in a solid color or with stripes of any color you like.
My mom started with ch 139.
Row 1: dc in 4th ch from hook, dc in next ch, go back and make dc in skipped ch prior to 1st dc, *skip next ch, dc in next 2 ch, go back and make dc in ch skipped* across, dc in last ch.
Row 2: ch 3, turn; *skip next dc, dc in next 2 dc, go back and make dc in skipped dc* across, dc in top of turning ch.
Repeat Row 2.
For the trim, my mom used single crochets along the shorter side and double crochets along the long side, then reverse single crochets all the way around the perimeter of the blanket.