Thank you. It's in her shoulder - right near the joint so it's really high up.
Considering that a typical front leg amputation removes the entire shoulder, including the scapula, this shouldn't be a reason that it's 'inoperable.' The top of the humerus is one of the most common locations for osteo. If amputation/chemo is an option you would want to consider, I'd suggest a second opinion, perhaps even ask for referral to a specialist. There are many other reasons to decide not to pursue definitive treatment with amp/chemo, and many opt to go with palliative care, but just wanted to mention this if it was something you did want to consider.
So sorry to hear about Hailey's diagnosis, especially so soon after everything you just went through with Sara.
This is where my Diamond's was, and I took her to OSU for amp surgery. She was 12 and did very very well. She had a very good 6 months until OS hit another leg bone.