The "ki kasar" associated with Mother Mary is likely referring to the observance of the Assumption of Mary.

• The Assumption of Mary: This is a Christian belief, primarily in the Catholic and Orthodox traditions, that at the end of her earthly life, Mary, the mother of Jesus, was taken bodily (i.e., body and soul) into Heaven.

While the term "ki kasar" might be a local or regional expression, the underlying concept points to the celebration of the Assumption of Mary. The Catholic Church celebrates the Solemnity of the Assumption on August 15th.

For further information, you can refer to these resources:

• Encyclopaedia Britannica - Assumption of Mary
• Catholic Encyclopedia - Assumption of Mary