Her baby is 20% breastfed; can she not fast?

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For pregnant women and breastfeeding mothers who do not fast, they have to make up the missed fasts and it is not enough for them to feed the poor
She has reached the age of puberty but she is not strong enough to fast

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Related Answers:
She is not sure whether she became pure before Fajr; should she pray and fast?
Are these people obliged to fast? Are they obliged to make up the fast?
How can she make use of her time when she is cooking in Ramadaan?
For pregnant women and breastfeeding mothers who do not fast, they have to make up the missed fasts and it is not enough for them to feed the poor
She has reached the age of puberty but she is not strong enough to fast

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