1.   The two cats curled up together in the armchair.

2.   In colder weather, your cat will curl up into a tight, heat-conserving ball.

3.   The cat would curl up, tightly like, and just go to sleep.

4.   The cat curled into a ball and went to sleep.

5.   Most of us have seen our dogs and cats curled up together, sometimes even grooming one another.

6.   Our cats curl up with them.