Genesis 21:8
ESV - 8 And the child grew and was weaned. And Abraham made a great feast on the day that Isaac was weaned.
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Every day when I watch the news I still see high infant mortality, e.g. Yemen, and I see many poor women feeding children sugared water because they have lost their milk; even if we have infant milk formulas in the West not many people in poor countries can get hold of them.
Weaning is still a very important part of a child's life.