What rights does adopted child have in property, alongwith own child?

We would like to inform you that on a valid adoption, the adoptee gets transplanted in adopting family with the same rights as that of natural-born son. Adopted child becomes coparcener in Joint Hindu Family property after severing all his ties with natural family.

So basically, the adopted child has exactly the same rights as a natural born legitimate child. This is mentioned in the Hindu Adoption and Maintenance Act and this view has even been enunciated by the Hon'ble Supreme Court of India.