The kitten ate half of it on the first day, but it was not enough. She ate another one.

The next day, it ate half of the remaining fish and another one.

On the third day, according to the old method, it still eats the remaining half first, and then eats another one.

On the fourth day, mother cat found that there was only one fish left.

Do you know how many fish father cat caught? How many fish does the kitten steal every day?