The Humane Society of the United States has an excellent guide to providing for pets in estate plans. A link to their guide is shown below.

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Knowing that pets usually have shorter lifespans than humans, you
may have planned for your animal friend's passing. But what if you are
the one who becomes ill or incapacitated, or who dies first? As a
responsible pet owner, you provide your pet with food and water,
shelter, veterinary care, and love. To ensure that your beloved pet
will continue to receive this if  something unexpected were to happen
to you, it's critical to plan ahead.

Learn what steps you can take to plan and provide for your pet's future without you by following the links below.

NOTE: The following information is intended to provide a general
overview and to stimulate your thinking about providing for your pet in
the event of your incapacity or death. It is not intended to provide
legal advice and is definitely not a substitute for consulting a local
attorney of your choosing who is familiar both with the laws of your
state and with your personal circumstances and needs, and those of your
pets.

Pets in Estate Plans Fact Sheet

SOURCE: Humane Society of the United States