My only suggestion is to make sure she knows the interest is there and assuage any concerns - she doesn’t sound like she is currently in need of funds so her issue may be forever home, ensuring he comes back if you can’t keep him (opposed to you selling him and he end up in a bad situation), her standards of care, etc.
I have seen all kinds -
One person was on her 20th year leasing the same horse when I knew her. Owner just refused to sell even though she rarely visited and never rode. Leasee wanted control of vet/end of life type decisions and also worried that owner would take horse back suddenly. She just kept offering, owner kept refusing.
I know someone else that leased a horse out and kept trying to get the long term leasee to buy horse but person kept refusing but leased for 5+ years when I knew about it.
I know horse dealers that have that one or two special horses they won’t give up for anything. They are leased out but won’t sell for whatever reason.
That’s how life is - just keep making sure the offer is on the table.
