baby bootie pattern help

I am crocheting a pair of cowboy booties and have a question about one of the rounds. At the end of the 4th round I have 43 sts. The 5th round states: working on heel of sole, center 13 sts. Working in front loops of rnd 3, with brown, join with sl st in first of 13 centered sts, sc in 11, sl st in next. Fasten off.
I am not sure about the centered sts part. How many sts should I have at the end of this round? Thank you for your help.