After grandma dies, will the property go to their children or their grandsons or granddaughters or her husband?

I can only answer questions about Idaho, USA.

You're asking me about the law in India? I'm only licensed in California.

In Illinois, if there is no Will, the decedent's probate estate will be distributed in accord with the statute on descent and distribution. If the decedent's spouse is living and the decedent had children the spouse will receive of the estate and the children will equally divide of the estate. The descendants of a predeceased child of the decedent will equally divide the portion that would have been received by the predeceased child if the predeceased child were alive. Example: living spouse and three children, 2 children living and 2 grandchildren (the children of the deceased child); spouse receives, each living child received 1/6 and each grandchild receives 1/12. If there is no spouse the children equally divide the decedent's estate, with the descendants of a predeceased child equally dividing the share that would have been received by the predeceased child. Children include any child adopted by the decedent.

Depends upon the question of whether grandma has a will or a trust and disposed of the property by her direction in either one of those documents. If no will, then the property is divided between her children, and any surviving issue of her predeceased children.

No way to say without more facts. Where is the property? Who is/are the owners? How is it owned, (i.e. joint, tenants in common, sole ownership)? What do the estate plans, if any, provide? There are a number of different possibilities depending on the answers to the above questions.

If no grandfather and no will, to her children in equal shares.

IT DEPENDS ON HER WILL AND THE LAWS OF HER HOME AND OF THE PLACES WHERE THE PROPERTY IS LOCATED.