Phoenix as Pets

Phoenixes are very difficult to domesticate, as Newton Scamander says in his book Fantastic Beasts and Where to Find Them:
"The phoenix gains a XXXX rating not because it is aggressive, but
because very few wizards have ever succeeded in domesticating it." There are two known domesticated phoenixes, one Albus Dumbledore's pet phoenix Fawkes, and the other Sparky the team mascot for the New Zealand Quidditch team the Moutohora Macaws.

Phoenixes that have been domesticated are extremely loyal to
their owners, and would depart to find their own paths if their owners
die, rather than finding a new master.