Nikaah & Marriage Issues

Validity of nikaah if mahr was not mentioned at the time of nikaah

Q: Zaid conducted the marriage of Zainab to Shuaib. But Zainab did not appoint Zaid as wakeel. However Zainab heard the ijab and qubool through the phone and then later when she was asked whether she accepted the nikaah with Shuaib, she said that she accepted. However, she did not notice what was the amount of mahr which was mentioned. So she has no idea about how much mahr she is going to get. Is the marriage valid?

Children born with disabilities due to marrying in the family

Q: In Islam, is cousin marriage allowed?

Medical science says that cousin marriage is wrong because it causes disabled children. Yes, there are many cases where children are completely fine but there are many cases where children are disabled because of cousin marriage.

My Conclusion: cousin marriage is risky.

Please advise me whether we should do cousin marriage or not? If your answer is yes then how can we overcome this risk?

Attributing an adopted child to the adopted father

Q: My uncle in law adopted my brother at the time of my brother's birth, and my uncle's wife breastfed him. Can my uncle be my brother's real father?

In my brother's nikah, if my uncle in law does not declare that he is the father, but the girl knows who the real father of the boy is, is the nikah correct?

Can my uncle in law write his name as the father of my brother?

Hurmat-e-musaaharah between males

Q: Does hurmat mushaharah become established if a person hugs his father but he has strange feelings in his private part. He was scared during the event and did not get a full erection, however he is not sure about any minor movements that he did not notice. But he thinks that the minor movements (very small movements) were because of nervousness. He did not get any sexual thoughts. He was also a little bit scared during the event.