Fathwa, - Her husband did not tell his new wife that he can not have children

Question
Im first wife of my husband and i know he can not have children,he
told me about this before merryd,its also confirmed by doctors.He got
merry second time but he didnt inform her that he can not have
children.I feel in some way quilty that i am aware of my situation and
she doesnt know anything and have hope that he will give her
children.I feel sorry for her much more because she is very young and
would have chance to have happy life whit children and in my opinion
my husband cheated on her,dont telling the true about his healt
condition before merryd her.Do i should inform her about this?Will it
be sin for me if i tell her?I told my husband that she should know and
he should inform her but he doesnt want to do it.I think he doesnt
want to tell her because if she knew she would never merryd him.
Answer
All perfect praise be to Allaah, The Lord of the Worlds. I testify
that there is none worthy of worship except Allaah, and that Muhammad,
is His Slave and Messenger.
If the matter is as you mentioned that doctors confirmed that your
husband could not have children, it was obligatory for him to inform
his second wife of that before marrying her because concealing this
from her is considered cheating. For further information, see Fatwa
87814.
Nevertheless, you should not tell her about that because she may be
contented with living with him even without having children. Besides,
it should be noted that some scholars are of the opinion that it is
not obligatory for the husband to inform his wife of his infertility
as long as he is able to have sexual intercourse. This is a strong
opinion.
Allaah Knows best.