1. Is it good to give our seed phrase or wallet password to our next of kin while we are alive since death is inevitable?
Imo, I don't think that would be necessary. All that matters is that he/she is aware that you do hold a few sats.
My reason for saying this doesn't have anything to do with trust. Its just a way of treating the whole thing as a regular inheritance and not something you unveil before hand. If you as a parent holds the seed phrase, at least, it should be somewhere around the house
(probably where you keep your stuffs), or the location should be specified on a will instead.
So, I'm of the opinion that there is no point of sharing such a sensitive information. Them being aware that you hold a few Bitcoin, should be more than enough.