Purchase of Plot

Dear Sir, I would like to purchase a open plot whose owner is died on 18-11-1998. The deceased plot owner is survived by his mother, wife, two married daughters and one married son and the deceased plot owner’s father is expired. On 16-06-2012, the said plot was registered by way of Gift Settlement Deed in favour of said deceased plot owner’s two married daughters by his wife and one married son by producing the death certificate of the deceased plot owner (plot owner’s mother is not involved in the registration and as I already said father is expired). The deceased plot owner’s mother is living separately and is not having good relations with the deceased plot owner’s other family members i.e. his wife, daughters and son. Since the deceased plot owner’s mother is living separately and not having good relations, even her whereabouts are also not known to anybody i.e. where she is living, whether she is dead or live etc. When I approached a Lawyer, he advised me as follows: “It is true that “mother” is a class I heir to a deceased Hindu. But she should have exercised her right before the transferees perfected their title to this property by possessing it adversely for more than 12 years (1998-2012). In the absence of such an act, by the mother, the transferees in gift deed have perfected their title to this property by adverse possession.” 1) Can I follow the above advise. 2) Can I purchase the said plot. 3) Or is there any way to purchase the above plot (Because the said plot is having a vastu problem. That’s why, the owners are selling the plot far below than the market rate. But, I am owning a plot adjacent to this plot If I combine both the plots as per vastu it is perfect. That’s why, I am interested to purchase the said plot) 4) Are there any legal problems in future from the deceased plot owner’s mother or from any other angle? Please advise.