Look up and learn Rav Dessler in Kuntres Hachessed in the first volume of Michtav MEliyahu. He describes that real love is created by giving. Juxtapose a birth parent who has not seen a child in 30 years since the birth and an adoptive parent who has been giving their all to raise an adopted child for 30 years. Undoubtedly at the end of 30 years the adoptive parents will have much much more love for the child than the birth parents. Giving (hav) creates ahava!
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