hi good wishes to u and your mother
the lumps you are discussing it might be lipomas or Neurofibromas.
it moves when we touch it if it is a lipoma with no pain these are not harmful ,only we can treat them through surgical excission only.
second opinion in view of neurofibromas it will be of two types mostly in type 1 it wont be painful type 2will be painful it needs treatment .
mostly these will be gentical in origin
it may spread to the hands,back etc in other areas tooo.
so far as per your details its my opinion .
clear history from your side will be needed to evaluate further mean while u can consult a general surgeon.