married daughter right ?

RESPECTED SIR ,

                             MR. X BROUGHT A PROPERTY FOR THE NAME OF HIS 2 CHILDREN ONE DAUGHTER AND ONE SON .THE BOTH CHILDREN ARE MINOR WHEN PROPERTY PURCHASED .NOW THE MR X EXPIRED AND THE CHILDREN ARE MAJOR .BOTH THE CHILDREN MARRIED .

                              NOW THE QUESTION IS THAT -

                                                                                   NOW THE SON OF MR X SALE THE PROPERTY BUT THE DAUGHTER OF MR X NOT WANT TO SALE THE PROPERTY .AND SHE SAYS THAT HE CAN NOT SALE THIS PROPERTY WITHOUT MY SIGHNATURE  SO THE SON CAN SALE THE PROPERTY WITHOUT HIS SISTER PERMISSION .CAN HE SALE OUT THERE SHARE FROM HIS PROPERTY .