Accepting a gift from one's na baaligh sister

Q: I was studying Arabic and my sister, who was about 11 or 12 years old, gave me an Arabic learning book that my uncle gave to her. I would use this book for my class and then at some point after, I mentioned to my father that she gave me the book and my father didn’t object to that.

I have recently been told that this was not a valid gift and a Wali can’t hand over the property of the child and that the gift of a child to an older person is not permissible. The father is also not allowed to give or allow the gift of his child without something in return. If at the time I thought this was valid, such as the Wali knowing (my father), what should I do?

Cutting one's nails and hair after one's qurbaani animal is slaughtered in another country

Q: A person refrains from cutting his nails/hair due to performing qurbani.

He follows Saudi for Eid (20th of July) whilst his wakeel doing the qurbani for him does so on Eid day in India (21st of July).

Does he therefore need to spend his Eid with long nails etc until the wakeel has slaughtered his animal the next day? If so, he also has no way of finding out what time of the day on the 21st the animal will be slaughtered, so how does he know what time of the day to cut the nails/hair?

Burying relatives in the same grave and desiring to be buried near the pious

Q:

1. What is the status of burying relatives together in the same grave? For example, husband and wife, or grandmother and grandson, or even cousins etc. Is it a matter of ease and identification or is there benefit for the mayyit and the like?

2. Also, will it be right to delay the burial so that an existing grave could be dug up in order to bury relatives together? If so, how long of a delay will be tolerable? In other words, the qabrastaan has a grave open already but a relative grave is wanted instead, so that has to be dug out and prepared and that constitutes some delay.

3. Is it wrong to have a desire of being buried with a certain person, because it means one does not desire burial near Nabi (Sallallahu Alayhi Wasallam) in Madina Shareef? For example, a person desires that he is buried near his mother. Or a person desires that he is buried near his pious Shaykh or pious Ustaad. So does this desire constitute disrespect to Nabi (Sallallahu Alayhi Wasallam) because nobody is greater than Nabi (Sallallahu Alayhi Wasallam) and/or burial in Medina Shareef?

Like someone says, "I want to be buried near my Shaykh" - so is that constituted disrespect to Nabi (Sallallahu Alayhi Wasallam) and Madina Shareef?" I am asking based on arguments someone gave to me.