Kitten Rehoming - Urgent

We found a kitten a few weeks ago, she was very hurt and needed surgery. We paid for the surgery, but we already have two cats and are having a hard time relocating her. The oldest of our cats is not nice to her at all, so she can NOT be left alone with him. And we have an urgent family matter to attend out of town, so I need to find a new place for her by Wednesday. Fully litter trained, good with kids and other cats (my other cat plays with her a lot).