Repeat the following Novena prayers every day for 9 consecutive days.

Holy Souls in Purgatory,
you are the certain heirs of Heaven.
You are most dear to Jesus
as the trophies of His Precious Blood
and to Mary, Mother of Mercy.
Obtain for me through your intercession
the grace to lead a holy life,
to die a happy death
and to attain the blessedness of eternity in Heaven.

Dear suffering souls,
who long to be delivered
in order to praise and glorify God in Heaven,
by your unfailing pity help me
in the needs which distress me at this time,
particularly

(Mention your request here...),

so that I may obtain relief
and assistance from God.

In gratitude for your intercession
I offer to God on your behalf
the satisfactory merits of my prayer and work,
my joys and sufferings of this day
(week, month, or whatever space of time you wish to designate).

(Assist at Mass and have a Mass offered for them, if possible.
Offerings of the Precious Blood and the Way of the Cross
are also powerful means of helping them
and obtaining their help.)