Hello there.
I can understand your concern.
is she a hypertensive?
the cause of the swelling could be related to her blood pressure,
hormonal causes,
kidney and
liver related causes.
you should consult a M.D consultant physician in person regarding this. run some tests and everything will be alright.
as of now ask her to sleep with pillows below her feet.
best regards,
Dr. Anil kumar jain.