Is an adopted girl considered a sister to the husband by Sharia, and is it permissible for her to kiss him as a brother, and is it necessary to disclose the truth of her lineage to whoever proposes to marry her, and is she treated like orphans?

The adopted girl is not considered a sister to the husband unless there is a reason for prohibition, such as fosterage (رضاعة). If she is a stranger (أجنبية) to him, it is not permissible for her to kiss him. The regulations for kissing a mahram (unmarriageable kin) must be observed. There is no need to inform the fiancé about the fact of her adoption. A child born of zina (unlawful sexual intercourse) is attributed to her mother, and she can be attributed to a general name to avoid embarrassment. This girl is treated as an orphan in terms of her guardian's entitlement to the reward for sponsoring an orphan.