I'm very sorry to hear of Ellis' passing to the RB. There's no question that our cats do feel emotion and mommy is missing her son. Just a thought, but have you considered adopting a senior kitty to keep her company? An older cat might be a bit calmer and cause less stress than a kitten during the adjustment period. This can be a tough call to make but you know your kitty and I'm confident that you'll make the best choice for all involved.