The Son's daughter Inheritance cases..
The first case..
She deserves the half if she is the only daughter.
"وإن كَانَتْ وَاحِدَةً فَلَهَا النِّصْفُ " .
"And if there is only one, for her is half".
The second case..
She inherits two-thirds, she and the other son's daughters.
. لقوله تعالى " فَإِن كُنَّ نِسَاء فَوْقَ اثْنَتَيْنِ فَلَهُنَّ ثُلُثَا مَا تَرَكَ"
"But if there are [only] daughters, two or more, for them is two thirds of one's estate."
The third case..
She inherits legally one-sixth with the other son's daughters who have the same degree and also with the bodily daughter, to complete the two-thirds which is for the two bodily daughters, as in the following Hadith..
"سُئِلَ أبو موسى عن ابنةٍ وابنةِ ابنِ وأختِ ، فقال: للابنةِ النصفُ، وللأختِ النصفُ وائِتِ ابنَ مسعودٍ فسيُتابِعُني . فسُئِلَ ابنُ مسعودٍ وأُخْبِرَ بقولِ أبي موسى فقال : لقد ضَلَلْتُ إذًا وما أنا مِن المُهْتَدين ، أقضي فيها بما قضى النبيُّ صلى الله عليه وسلم: للابنةِ النصفُ، ولابنةِ الابنِ السُدُسُ تكملةَ الثُلُثَيْنِ وما بَقِيَ فللأختِ"
"The daughter gets half and the son's daughter gets a sixth, completing two-thirds, and what remains goes to the sister." Al-Bukhari.
The fourth case..
If there's grandson, or son of grandson with the son's daughter, she needs him to inherit, so he inherits by agnation, after giving the entilted shares.
" ألحقوا الفرائض بأهلها فما بقي فلأولى رجلٍ ذكرٍ " .
"Give the shares to those who are entitled to them, and what is left from those who are entitled to it goes to the nearest male heir."
The son's daughter inherits with him as an agnate relative, this is divided: the male takes the share of two females as Allah said:
"يُوصِيكُمُ اللهُ فِي أَوْلاَدِكُمْ لِلذَّكَرِ مِثْلُ حَظِّ الأُنثَيَيْنِ " . سورة النساء.
"for the male, what is equal to the share of two females".
Excluding the son's daughter from inheritance...
A- The son's daughter is excluded (deprived) from inheritance if the deceased has son, or grandson who has higher degree than her.
B- the son's daughter is also excluded (deprived) if there are two or more bodily daughters, or if there are son's daughters in a degree higher than her, on the condition that there's no agnate relative to the son's daughter in her degree or lower than her.
C- the son's daughter is lowered from the "half" to the "sixth" if she has a female heir in a degree higher than her.