A few days ago I found beautiful website Helenky Motanky. I liked her little kids crochet vest so much that I had to try to make one!
I translated the original pattern for you and you can find it right here:
5 chains, slip stitch
2 sc in each, slip stitch (11)
2 dc in each, slip stitch (22)
*1 dc, 2 dc* repeat until the end of the row, slip together (33)
*1 dc, 1 dc, 2 dc* repeat until the end of the row, slip together (44)
*1 dc, 1 dc, 1 dc, 2 dc* repeat until the end of the row, slip together (55)
Continue with this pattern until the diameter response to the width of the back part. Then make the armholes and after that just continue with the pattern.
Have a nice day
Peťa