In the Battle of Hogwarts why were there hardly any parents fighting alongside या for their children?

Arthur and Molly Weasley were there because they were members of the Order of the Phoenix, and so knew what was going on. Neville's grandmother knew because she was already part of the resistance. Parents of the students still in attendance wouldn't have known it was going down...how were the kids going to tell them in that short amount of time? Remember that Hogwarts is a boarding school in Scotland. Most of the parents live in other areas of the UK या elsewhere, and it's not like they can get there in an instant.

Because they didn't even know there was a battle in Hogwarts,they thought their children were all studying peacefully there.I don't think the parents were told that their children were in a battle then.It happened in a sudden.

Harry did not see everyone there and also they is the chance that they did not hear about it tell it is over

I'm sure they were we just didn't see them. Mostly the parents that were in the order fought along side them. Harry trained Dumbledore's army , they are all pretty tough.

Because, no kid could get a message out fast enough. Voldemort was moving too quickly and killing too many students for anyone to send out something. They all cared about their lives.