Their father’s wife breastfed a baby girl – is she regarded as their sister?

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Check below answers in case you are looking for other related questions:
Each of them breastfed the child of the other; do any rulings result from that?
The children of your father through breastfeeding from his second wife who did not breastfeed you are siblings to you

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Related Answers:
He was breastfed by his maternal grandmother, along with his maternal cousin; what is the ruling?
She breastfed a child thinking that it was her son; is the mahram relationship through breastfeeding established?
Ruling on breastfeeding and the wisdom behind it
Each of them breastfed the child of the other; do any rulings result from that?
The children of your father through breastfeeding from his second wife who did not breastfeed you are siblings to you

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