Is it permissible for a wife`s family to demand her husband to divorce her although she doesn`t want that?
                                It is forbidden for them to do that in case their daughter doesn`t want divorce unless there was a sin that continues as long as the marriage survives.
                             
                        
                            
                                
                                If someone unknowingly bought stolen cement multiple times, and if the seller is revealed, will my husband bear any sin?
                                The sin of the theft falls on the one who stole. However, the person who used the cement must pay its value to the rightful owner from whom it was stolen, and then seek reimbursement from the seller. If the thief compensates the rightful owner, there is no liability on the person who used the cement. And Allah Almighty Knows Best.
                             
                        
                            
                                
                                Is it permissible for a woman to wear underwear while performing Umrah?
                                Yes, it is permissible for a woman to wear underwear while performing Umrah. This is because she should keep her regular clothes that cover all her body while being in a state of Ihram (ritual consecration) for Hajj, or Umrah. However, she should uncover her face and hands, but it is permissible for her to let her head-covering garment drape from her head down over her face when non-Mahram (i.e., marriageable) men pass by her. And Allah Knows Best.
                             
                        
                            
                                
                                Is the maternal uncle of one`s mother a Maharam?
                                All perfect praise be to Allah the Lord of The Worlds. May His blessings and peace be upon our Prophet Mohammad and upon all his family and companions.
Mother`s maternal uncle is a mahram. And Allah The Almighty Knows Best.
 
* In Islam, a mahram is a member of one's family with whom marriage would be considered haram, concealment purdah, or concealment of the body with hijab, is not obligatory; and with whom, if he is an adult male, she may be escorted during a journey, although an escort may not be obligatory.