Mother remarrying

Q: My husband and I have a daughter Alhamdullilah and Allah has blessed us with twin boys who will be born soon In Shaa Allah. I am stuck as to what to do. My mother who has decided to marry again this will be her forth marriage but this choice has made both myself and my sister very unhappy we are heartbroken about it as she has before gotten married without our knowledge. Now this time she has told us that she made this choice and did not ask our opinion or how we felt. I know it is Sunnah to be married, but this decision has caused so much pain to my marriage as well as my husband is always saying really bad things about her and I am constantly having to pick sides. I cannot find a way to solve this I am suffering but cannot explain to my husband that she is still my mother and I need to respect her but what if I can never accept her decision to marry again. I don't want my children to suffer as well and I am afraid this will cause her to not meet with her grandchildren. May Allah guide in this difficult time. Based of the above. Is what my mother is doing correct by choosing to marry over the heartbreak of her children?

Changing one's name after accepting Islam

Q: I was Hindu and married a Muslim guy and converted now. I want to know is it mandatory to change name to Islamic name? I heard many YouTube scholar speeches where they say it isn't necessary to change the name. If it doesn't have any bad meaning of something related to other religion, my name has no bad meaning nor it is Sanskrit name. It isn't Hindu name at all and it doesn't associate any other gods names too. Please reply, they have changed my name for marriage purpose and have affidavit but I don't want to get it changed in documents as I also heard that we can visit mecca by just having proof of conversion and affidavit and marriage certificate. Please advise. I'm emotionally very much attached to my old name.

Looking after one's mother

Q: I have a question relating to a child's obligation toward parents. I want to ask question relating to family vacation or social activity. If a wife and husband work jointly to pay for a family vacation and the mum wants to go on holiday as well, I have a question:

1) Can a credit card or credit facility be used to fund the mum's holiday?

2) Can the mum travel without a mahram if she is over 60?

What is the obligation of the son in this regard? Can he politely decline the payment of the holiday due to inadequate funds and also disallow the holiday as no mahram is present? Will the son be punished in the eyes of Allah for doing this? Also what happens when the money one's son gives to a mum on debt and that is being used to buy lavish gifts for the other son and his family? What happens in essence if a mum thinks a child has the financial means and expects all expenses and holidays to be paid for when a child in essence is living on finance?

Secret Nikaahs

Q:

1. Is there a difference in nikaah and marriage?

2. Is it permissible to have a nikaah with someone else even when you are married?

3. Is it compulsory to have permission from wife and children (all well grown up) to have nikaah with someone else (due to total / negative and un acceptable cooperation in life from wife)?