Contemplating whether to have a child

Q: I have two children both under 8 and my wife wants a third child. I'm 49 and my wife is 35. My mother feels that I'm too old to have any more children. My wife feels she's still young and would like another child. My mothers reasoning is that with my age I might not see my child grow up and leave my wife with having to look after three children. Should I go with my wife's wishes or is my mothers views correct. What is the Islamic ruling and advise in regards to this situation.

Intending to get married

Q: I am a 17 year old girl, currently in my final year of high school. Recently, I've been having a lot of thoughts about marriage and the purpose of a Muslim's life. I reasoned that there is no point in studying for many years only to die and end up without any knowledge of Deen. Hence I decided to get married once I'm done with high school. What are your views on this decision? 

Network marketing

Q: I have a question relating to network marketing.

I am a neolife distributor and I sell the products as well as recruit people under me, thus growing my team. I therefore earn based on their sales as well as my own.

My question is whether this is allowed by the shariah. Is the income earned from what they sell and thus contributing to my points and therfore my position within the company e.g. Senior manager, Halaal income?

Meaning of Hadith where people will give testimony before they are asked for it

Q: What is the signification in the following narration about:"They will give testimony before they are even asked for it.”

Imran ibn Husayn (radiyallahu ‘anhu) narrated that Rasulullah (sallallahu ‘alayhi wasallam) said:

“The best of people are my generation, then those who follow them. Then, after them a people will come who increase in fatness, loving fatness. They will give testimony before they are even asked for it.” (Jami’ Tirmidhi)?

Buying a cheaper ticket and showing the company a higher price

Q: I'm going to my home country on vacation from Saudi Arabia and my company is giving me an air ticket of 2090 Saudi Riyals. I told them that I will buy it myself.

If I buy a cheap ticket in a less privileged airline and show them an invoice of a privileged airline, the same that the company was supposed to buy for me. Kindly tell me if it is okay or the surplus money will be haraam.