Fiona:

    a most difficult situation made more so by you inability to see them,
what the body language.....

     can you discuss with mom things that could contribute to a delay let
down to see of any of these factors might fit? ... ie: stress, tension, mixed
emotions, difficulties at home, work.....

     the other thought is might she be misreading what is happening.... ie:
mom "ready " to feed and infant wants to play?

      good luck....

                       Patricia