Replying to Using an undersized ski

HelloNewSchoolers! Long time lurker, first time poster.

I'm taking my 4yo for her first time and to make things easier, I'm considering using a small ski while I'm with her on the bunny hill. Does this make sense, or am I going to have issues?

I'm 6'3, 200lb, and usually 170-180cm fits me well.
I have an older K2 that's 136cm and has adjustable demo bindings. Any reason why this would be a bad idea to use on the bunny hill?