ДНК S06E25 - Выпуск 742. Два подкидыша одной матери?

In November 1984, a child was found abandoned at a bus stop in Astrakhan. Four years later, in the same city and in the same area, a newborn girl was found in the entrance. Now a 38-year-old man and a 34-year-old woman are sure that they are blood brother and sister of the same mother-cuckoo. But foster families are not ready to accept a newly-made sister and brother without a genetic examination. So is there one mother cuckoo in abandoned children?