Button holes/circular knitting

I want to make this for my neice:


But as she’s three, I expect she’ll (inconveniently) grow at some point over the next year. As I’d like her to get a bit more than 1 month out of it, is there a way I can make this, with a split and button hole at the top or is that impossible in circular knitting?


Just start the pattern working back and forth instead of in the round and add a button hole after a few rows. When you get to the point where you think you have enough at the top to accomplish your goal (3-4 inches or so at the top?) then join and begin working in the round.

Ooh, That sounds a lot easier than I thought it would be, didn’t realise you could transfer from back n forth to ITR like that.