In 1999, United Nations proclaimed February 21st as International Mother Language Day as a way to promote linguistic and cultural diversity. This date was chosen in recognition of the 1952 Bengali Language Movement in what is now Bangladesh.
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My “Abbu” (father) came from a Bangla-speaking family while my Ammu (mother) hailed from a Urdu-speaking family. It’s a common phenomenon in Bangladesh because before the 1971 war, we used to be East Pakistan and families that spoke both languages lived in both East Pakistan (now Bangladesh) and West Pakistan (now Pakistan). Growing up, my brother and I spoke both languages, at home we spoke Bangla and in my maternal grandparents' house we spoke Urdu/Hindi mixed.