Saying out of the empty bath tub?

[newkittyowner]

We have two kittens born in April. Their litter box is in the upstairs bathroom and there is also a bath tub which our kittens have decided would be fun to play in, sit in, lay in etc. They track litter into the tub which is annoying. Our three year old son has baths in it and its getting really tedious and tiring to have to clean the bath tub every time it's bath time. He is the only one that uses the bath tub and he won't have one in ours in our bedroom.
So my question is if there is anyone have any suggestions of how we can keep them out of the tub, something harmless to put in that will keep them out or am I just going to have to live with cleaning the bath so much?

 

[mservant]

You could try the sticky tape method that has been suggested for work tops on this site?  Don't see why it shouldn't work anywhere. A few days of having to put on and take off the tape at bath times has to be better that cleaning up the tracking.