A child is a woman's son even if she has no other children as long as he has suckled from her
The breastfeeding that affects marriageability refers to breast-feeding a baby for five times or more during the first two years of the baby's life. One breastfeeding is counted when the baby holds the breast and sucks milk from it. If the baby releases the breast to take a breath, for example, and holds it and sucks milk again, this will be counted as a second time and so on.If the baby boy mentioned above was breast-fed by his paternal aunt for five times or more during the first two years of his life, he would be considered her son by breastfeeding even if she had no children. However, if the baby boy received less than five times of breastfeeding or he sucked no milk from the breast, he would not be considered her son by breastfeeding.May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.