Property inheritance by Christian heirs

I have read articles on other websites which mentions that the benefit of buying flat in joint names of husband & wife is that after the death of one of the spouse, the other spouse automatically becomes the owner of the flat. I have also read in other online articles that after the death of the husband, the wife will become sole owner of the jointly owned flat only if the husband has made a WILL in which the husband has mentioned that after the death of the husband, wife will inherit the entire flat. Kindly clarify the correct law applicable to Christians living in Mumbai regarding the following: Facts: 1. Flat in Mumbai jointly owned by husband & wife. 2. Husband dies without making a WILL 3. In the purchase agreement of the flat, husband’s name is written first and wife’s name is written second. 4. Entire cost of purchasing the flat was paid by husband. Kindly clarify: 1. What is the share of the wife in the flat after husband’s death? 2. Whether wife becomes the sole owner of the flat after husband’s death? 3. After the death of the father without making any WILL, whether the children (all above 30 years of age) have any inheritance in the flat jointly owned by father & mother?