I don't agree with -打手手.
During her age it is normal for them to touch and discover their own interest. They are not naughty. The only way is like what your 99 did-- to provide a safe environment for them. But you could buy some protection net instead of turn the fan off.
Otherwise you would complaint about that your child 打 other child soon. As they would learn from you.
This is my own opinion as my boys were also very naughty and curious when they were young.