It certainly gives us pleasure to realise the general level of awareness in health matters. At this moment in time, Stem Cell therapy has not evolved to a stage where it can be told to be universally applicable. Umbilical cord cells are being preserved for use in later years in life. It can be of use to child himself if he develops any disease process later in life. I am very doubtful if these cells can be of any use to your father because:
(a) They may not be immunologically competent and compatible.
(b) Also the time that it would take for the technology to evolve is still sub-judice and may be reasonably long.
So I suggest if you so wish, you can preserve the umbilical cord of your baby and if something new breaks through in the new foreseeable future in any case, that can be used for your father. Though it seems little unlikely in our present stage of evolvement of stem cell therapy.