Keiki with no roots and mother

[Prr]

Hi
My Phil had a keiki (2 leaves about 1 inch, on tiny is growing), but my mother plant suddenly died within 4 days! Leaves just went yellow and that was it. No idea why... I decided to save the keiki and cut the stem off and put it in a vase filled with water. No it has been there for 4 months, looking beautiful and alive and has grown 1 leaf in addition to the 2 previous ones, but still has no roots.
Any advice, what should I do?

Thanks