Sadly, I believe this plant has expired. The psuedobulbs appear to be dessicated and mostly likely rotted out. I see no new growth. The plant is/was way overpotted. The media looks old, far too much ground peat.

I agree with Toyo. The orchid is dead. Maybe you can purchase something similar as a tribute to your mother.
Did the blooms look like any of these in the link?

Here is a link that might be useful: Oncidium sub-tribe orchid blooms

This post was edited by arthurm on Thu, Sep 19, 13 at 13:42

It looks to me like it's potted in regular potting soil, orchids can't survive in that. They need orchid media.

Cathy