Can you kill a pet and charm a new one?

I have a pet but i want a other pet. How can i do this... When i let the pet die. I cant charm a new one...
can som1 help

Thx in advance

outside of post-searing ascalon in the explore area is a pet trader, talk to him and he will take your old pet, so that you can get a new one. there is also a pet trader in regent valley in pre-searing ascalon, beside the ranger trainer.