As a PP said, if they genuinely want to teach, then they should absolutely go for it, as regret isn't good. If they're just considering it as they're not sure what to do, then no, don't do it.
For me, the holidays are generally a positive. Although I can't take days whenever I want, I do like knowing when they are and not have to fight to book them like in other jobs I've had.
Pay is OK, but feels much better away from London. I've worked in London, the fringe and now about a mile into 'the rest of England', so earn the same as someone hundreds of miles away, but my mortgage is likely to be much larger, so the pay doesn't feel amazing for over twenty years' experience.
Be aware that it can be very difficult to leave a teaching job and go into another career due to the notice periods, which can be up to 7 months in England.
In many schools I've worked in, the bullying from management has been horrendous. Perhaps it's like it in other sectors, although not any I've worked in.
As for the positives, yes, the kids can be great. If you're secondary, you will hopefully be able to teach a subject you're passionate about (although not always the case).
Would I encourage my DC to teach? No, not unless they really wanted to do it. But there are many other careers I would discourage them from too. I'd be happy if they were happy.