Her brother is very audacious in committing sin – what should she do with him?

I ask Allaah to bless your brother with guidance and
righteousness, and to bring him back to the straight path, and to help you
to call him and guide him to what is good and to make that count in the
balance of your good deeds. 

You should note – may Allaah bless you – that there are a
number of ways in which you can call your brother and guide him. These
include the following: 

Firstly: Pray sincerely for your brother to be guided and set
aright, and have certain faith that Allaah will respond. Keep on praying for
that, and know that Allaah will never let down the one who puts his hope in
Him or refuse to answer the one who prays to Him with sincerity. 

Secondly: Try to advise him sincerely, seeking to convince
him rationally. Encourage him by telling him of the honour and great reward
that Allaah has prepared, and warn him by telling him of the punishment and
humiliation and severe torment that Allaah has prepared for the sinners.
Tell him about the true nature of this life, and that Allaah has only
created this universe – with its earth and heaven, seas and rivers,
mountains and plains, lowlands and deserts, for you, O man. How can you, O
weak creature, compare to these mighty creations which Allaah has subjugated
for you, to make your life easier, as Allaah says (interpretation of the
meaning): 

“He it is Who created for you all that is on earth”

[al-Baqarah 2:29] 

“He it is Who has made the earth subservient to you (i.e.
easy for you to walk, to live and to do agriculture on it); so walk in the
path thereof and eat of His provision. And to Him will be the Resurrection”

[al-Mulk 67:15] 

“See you not (O men) that Allaah has subjected for you
whatsoever is in the heavens and whatsoever is in the earth, and has
completed and perfected His Graces upon you, (both) apparent (i.e. Islamic
Monotheism, and the lawful pleasures of this world, including health, good
looks) and hidden [i.e. one’s faith in Allaah (of Islamic Monotheism),
knowledge, wisdom, guidance for doing righteous deeds, and also the
pleasures and delights of the Hereafter in Paradise]?”

[Luqmaan 31:20]

Indeed He has preferred
you above all these earthly creations, as He says (interpretation of the
meaning): 

“And indeed We have honoured the Children of Adam, and We
have carried them on land and sea, and have provided them with At‑Tayyibaat
(lawful good things), and have preferred them above many of those whom We
have created with a marked preferment”

[al-Isra’ 17:70]

If you know this, O weak creature, and that Allaah has
created all these great creations and subjugated them for your comfort in
this life, then hasten to ask the logical question which occurs to every
wise person: Why did Allaah create me then? Your Lord and Creator has
clearly answered this question, as He says (interpretation of the meaning): 

“And I (Allaah) created not the jinn and mankind except
that they should worship Me (Alone)”

[al-Dhaariyaat 51:56]

So the purpose for which you have been created, O man, is
this: To submit yourself truly and sincerely to Allaah, the One, the Only.
This is the answer to your question: for whom should I set myself straight?
You should set yourself straight for Allaah Who has created you and formed
you, Who has given you life, strength and health, and all the blessings that
you enjoy. They all come from Him alone, and if He so willed He could take
them all away from you in the blink of an eye. Does He not deserve that you
should your gratitude for these innumerable blessings by doing what He
commands and avoiding what He has forbidden, which is the essence of the
worship for which you were created. With regard to your saying why should I
set myself straight, Allaah has stated the reason why He created death and
life in this world. It is so that you may know the greater reality which,
once a man knows it, he cannot have any peace of mind until he attains the
pleasure of Allaah and meets Him in Paradise. Allaah says (interpretation of
the meaning): 

“Who has created death and life that He may test you which
of you is best in deed. And He is the All‑Mighty, the Oft‑Forgiving”

[al-Mulk 67:2]

So you should understand this and understand that your
Creator is testing you now, in this world, to see what you will do and to
recompense you accordingly on the Day when you meet Him – if it is good then
you will be rewarded and if it is bad then you will be punished – and you
should understand that after death man will never be left neglected, rather
he will be recompensed according to his deeds as Allaah says (interpretation
of the meaning): 

“Does man think that he will be left neglected (without
being punished or rewarded for the obligatory duties enjoined by his Lord
Allaah on him)?”

[al-Qiyaamah 75:36],   

Based on this, you will
notice that Allaah often describes in His Book what He has prepared for His
slaves who do good in this world, for in the Hereafter they will have with
Him Paradise that is as wide as the heavens and the earth, in which there is
what no eye has seen, no ear has heard and it has not entered the heart of
man. And He also often describes what He has prepared for those who do evil
and neglect His rights over them; it is blazing Fire in which they will
neither live nor die, in which He has prepared all kinds of humiliation and
torment which would cause a child’s hair to turn white if he heard of them,
let alone saw them with his own eyes. We ask Allaah to keep us and you safe
from it. 

After knowing all this, is it befitting for you to dare to go
against His commands or to live for any purpose other than that for which
you have been created? By Allaah the poet spoke the truth when he said: 

If when we die we are abandoned, then death would be the end
of every living thing

But when we die we will be resurrected and asked after that
about everything. 

Undoubtedly the anxiety and worry that you are feeling make
you wish for death; that is because you have lost the sense of this noble,
divinely-ordained goal. The greatest and most enjoyable thing in this
universe is to be a true slave of Allaah. So beware of turning away from
your Lord and becoming far away from Him, for you will return to Him even if
you live a very long life, as Allaah says (interpretation of the meaning): 

“O man! Verily, you are returning towards your Lord  with
your deeds and actions (good or bad), a sure returning, and you will meet
(the results of your deeds which you did).”

[al-Inshiqaaq 84:6]

Beware lest you meet Him
having turned away from Him, and the following words apply to you
(interpretation of the meaning): 

“But whosoever turns away from My Reminder (i.e. neither
believes in this Qur’aan nor acts on its teachings) verily, for him is a
life of hardship, and We shall raise him up blind on the Day of
Resurrection.

125. He will say: ‘O my Lord! Why have you raised me up
blind, while I had sight (before).’

126. (Allaah) will say: ‘Like this: Our Ayaat (proofs,
evidences, verses, lessons, signs, revelations, etc.) came unto you, but you
disregarded them (i.e. you left them, did not think deeply in them, and you
turned away from them), and so this Day, you will be neglected (in the
Hell‑fire, away from Allaah’s Mercy).’

127. And thus do We requite him who transgresses beyond
bounds [i.e. commits the great sins and disobeys his Lord (Allaah) and
believes not in His Messengers, and His revealed Books, like this Qur’aan],
and believes not in the Ayaat (proofs, evidences, verses, lessons, signs,
revelations, etc.) of his Lord; and the torment of the Hereafter is far more
severe and more lasting”

[Ta-Ha 20:124-127]

So hasten to repent sincerely, and you will find a Lord Who
is generous and rejoices over His slave when he repents, and is pleased with
him when he repents. Indeed He bestows such love and mercy upon him that has
never crossed anyone’s mind. So what are you waiting for? Allaah says
(interpretation of the meaning): 

“So flee to Allaah (from His Torment to His Mercy
– Islamic Monotheism). Verily, I
(Muhammad) am a plain warner to you from Him”

[al-Dhaariyaat 51:50]

Once you have understood this, then note – may Allaah help
you to do that which pleases Him – that this great blessing, salvation from
that painful torment and success in this great test can only be attained by
means of hard work and difficulty which requires patience, perseverance and
longsuffering. But it is a hardship that will quickly pass and suffering
that will soon end, to be followed by eternal bliss and everlasting
pleasure. What is a little hardship and pain when compared with eternal
delight and everlasting joy. 

We ask Allaah to bless us all with His bounty and His
Paradise… 

In conclusion, I would like to leave you with these great
verses from the Book of Allaah, which He revealed to His slave Muhammad
(peace and blessings of Allaah be upon him) to be a healing for the hearts
of the believers and a remedy for their ills, so read them and ponder their
meaning, so that Allaah may make them a balm and a healing for the anxiety
and distress that you are suffering.  

Our Lord said (interpretation of the meaning): 

“Verily, those who say: ‘Our Lord is Allaah (Alone),’ and
then they stand firm, on them the angels will descend (at the time of their
death) (saying): ‘Fear not, nor grieve! But receive the glad tidings of
Paradise which you have been promised!

31. ‘We have been your friends in the life of this world
and are (so) in the Hereafter. Therein you shall have (all) that your
inner‑selves desire, and therein you shall have (all) for which you ask.

32. ‘An entertainment from (Allaah), the Oft‑Forgiving,
Most Merciful’”

[Fussilat 41:30-32]

“Verily, those who say: ‘Our Lord is (only) Allaah,’ and
thereafter stand firm (on the Islamic Faith of Monotheism), on them shall be
no fear, nor shall they grieve.

14. Such shall be the dwellers of Paradise, abiding
therein (forever)-a
reward for what they used to do”

[al-Ahqaaf 46:13-14]

“O you who believe! Fear Allaah and keep your duty to Him.
And let every person look to what he has sent forth for the morrow, and fear
Allaah. Verily, Allaah is All‑Aware of what you do.

19. And be not like those who forgot Allaah (i.e. became
disobedient to Allaah), and He caused them to forget their ownselves (let
them to forget to do righteous deeds). Those are the Faasiqoon (rebellious,
disobedient to Allaah).

20. Not equal are the dwellers of the Fire and the
dwellers of the Paradise. It is the dwellers of Paradise that will be
successful”

[al-Hashr 59:18-20]

And there are many other verses which explain this great
truth clearly. So you must turn to the Book of Allaah, in which you will
find all that is good, and keep away from everything that is bad and evil. 

I ask Allaah to open your heart to goodness and to make you
steadfast in adhering to it until you meet Him; and to keep evil away from
you, for He is All-Hearing, Ever-Near. And Allaah knows best.