I am making a cardigan sweater for a child. The pattern creates a collar by increasing along the button hole edge. As you are creating this collar the pattern states the following:
When piece measures 45 cm. cast off outermost 17 sts for shoulder and continue in stocking sts over remining 15 sts as follows:
*2 rows garter sts over all sts, 2 rows garter sts over only the outermost 9 sts.* repeat from *-* until collar measures 5.5 cms.