How many sucklings are necessary for a child to become a brother by suckling? And do my eldest son and all my children become her children by suckling, and vice versa, if brotherhood is established between the two suckling infants?

Scholars have differed regarding the number of sucklings that establish prohibition. The fatwa adopted by us is that prohibition is not established except with five full, separate sucklings. The reference for defining a suckling is custom. A single suckling is when the child suckles and then voluntarily stops suckling. Therefore, two or three sucklings do not establish prohibition as long as they are fewer than five. The ruling of suckling applies only to the child who was suckled, so the wet nurse becomes a mother to him, and her children become his siblings. The siblings of the suckled child have no relation to this.