hi,thanks for query.Normally low blood pressure
unless causing problem need to be care for.At times due
to some stress
or improper intake it may go down to this level.In case of any problem your doctor
will try to look for the reason for this.She may need some mroe investigation like echo for heart and other blood tests to look for the cause.please ask her to take rest and have more fluids.
wishing her good health.