Bukhari

Hadith Commentary:
In the law of Islam, an adopted boy or girl holds no legal weight; they will not receive the same rights as biological children.

Hadith Commentary:
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Hazrat Zayd ibn Harithah radi Allahu anhu was the freed slave and adopted son of the Noble Prophet sallallahu alayhi wa sallam, and the Prophet had immense love for him. Similarly, Hazrat Zayd radi Allahu anhu also had a deep attachment to him.
His brother, Hazrat Jabalah ibn Harithah, narrates that he came into the service of the Messenger of Allah sallallahu alayhi wa sallam and said:
“O Messenger of Allah sallallahu alayhi wa sallam! Please send my brother Zayd with me.”
He (the Prophet) replied:
“He is present, and if he wishes to go with you (to Yemen), I will not prevent him.”
Hazrat Zayd ibn Harithah radi Allahu anhu said:
“O Messenger of Allah sallallahu alayhi wa sallam! I do not prefer anyone over you.” Thus, Hazrat Jabalah radi Allahu anhu says that he found his brother’s opinion superior and weightier than his own.
(Jami‘ at-Tirmidhi, al-Manaqib, Hadith: 3815)

➋
When Allah Ta‘ala intended to abolish the custom of the Age of Ignorance, He chose the adopted son of the Messenger of Allah sallallahu alayhi wa sallam himself, Hazrat Zayd radi Allahu anhu, for this purpose. Thus, after the revelation of the verse, he was called Zayd ibn Harithah instead of Zayd ibn Muhammad.
In any case, in Islamic law, an adopted child does not have such a status that he receives the same rights as real offspring.
(Wallahu a‘lam)