How to train a ferret

[destine198300]

My family adopted a male ferret over a year ago. He is a complete angel. We let him run loose around the house, and therefore, he goes where he likes(only in corners, or behind the toilet).
We do catch him in the litter box(we also have a male cat) a few times a day, but not enough to make a difference.

He is an amazing animal. He plays with my daughters(4 and 7), plays with my cat, my moms dog(when he comes to visit), and chases us around the house.

We absolutely love him. The only problem is, the peeing and pooing in the corners. I've heard that you could train a ferret to go in the litter box, and only the litter box. But I've had yet to find out how.

We've picked him up(when we see him going to the corner), we've picked up his poo and put it in the box...ect. But he has yet to keep going to the litter box.

Does anyone have any tips or ideas on what to do? It's gotten to the point that his pee has stained our hardwood floor in a corner.

Thanks