Don't underestimate a 9 yr old, they can surprisingly play some pretty damn good golf at that age. I'd work on everything: chip, putt, full swing, you name it. Make it fun, challenge and award them. I have a 5 and a 9 year old and you'd be surprised how exciting winning a quarter is. Coming home with 75 cents in their pocket is fun to a kid.
Is this 9 yr old athletic? At the age of nine, he/she should be able to grip the club like a "big person". Shouldn't take long if they listen well, the grip isn't too difficult to teach/learn.