sending one DC to private secondary but not the other

I hate to say it but whatever the kids feel about it now and however fair it seems based on their situations - when they are adults this could be a massive source of resentment.

I don't think any 10yo should have sole control of this decision.

But if DS1 is adamant then yes it's fine for him to go to the comp, and yes it's fine for DS2 to go to the private school, it's not unfair as you aren't "denying" ds1 anything - he doesn't want it.

In your shoes I would be putting aside the fees from now anyway to make later times less tight, and would offer DS1 the opportunity to try out for a transfer place into the private school for y9 once he has had a chance to grow up a bit more. Lots of private schools take a significant additional intake for y9.

I have a few privately educated friends who view their education as a disadvantage as they stand out as being posh and elitist. Particularly the ones that didn't achieve much (in their eyes compared to their peers). Private school isn't always the right option.

I have one in each.
State kid (older) didn't get through private entrance. There is nothing I can do about that. It's very fair - they are different kids.

It's much easier to support them through university. If you are already used to paying £15k worth of fees per year per child, dropping down to £6k uni maintenance top up is a breeze

We did this for ours, some went through private, some public. It was about the right fit for the child, and also what they wanted. Some wanted to go to the local high school with their friends and refused to consider anything else, and we knew they would be okay there, so no issue. None complained after the fact. We did have one who made the swap for senior years as at that point they realised another school may be a better fit for what they wanted and were more mature and realised they would still maintain their friendships while at a different school, and maybe make some more friends but were okay as well if that didn’t happen.

We did this.

Actually we started off by both dd and ds going to private schools. Dd got a 50% bursary to a school specialising in her area of talent, ds went to an academic school. We applied for a local state school but he didn't get a place and was allocated a school we did not like.

It became apparent that the private school was totally the wrong school for ds, he was very unhappy there and so we moved him to a different state school. He then chose to go to a state college to study a vocational subject whereas dd stayed private for 6th form.

This is a tricky decision and one we are also facing. Our DC1 would sooner chew his own arm off than go to private school. We tried to persuade him at 11 but he was having none of it. Now in year 9, he is in fact thriving at his state secondary school. However, for various reasons - similar to you (sports etc) we would like to send DC2 to private school and she is pretty keen on the idea. Sorry, not really helping but empathising and following for thoughts from others.

You give them both the opportunity. If one doesn’t take that opportunity, that doesn’t mean it is closed for the other. If ds1 has a choice then ds2 should get the choice too.

No it’s not fair to send one to private and the other not
they are to young to understand the privilege a private school education gives students ..
is this your way of justifying only sending one ,so it costs less ,by saying they made the decision themselves..

If ds1 changes his mind later then you could look into sending him from year 9 or year 12.

I'm from a big family and my parents must have covered every combo of schools possible by the time we had all finished, from top public school to local comprehensive.

None of us resent where the others went, and in terms of outcome we've all ended up in very similar salary brackets and lifestyles.

You've given DS1 the option - it's not as if you are doing Eton for the boys and local state for the girls or anything like that.

Maybe DS1 will want private for 6th form, or university in the USA or something that will even it out in your mind.

If it is a highly sought after very academic school, I would first find out how competitive it is to actually get in. As we have just gone through the 11+ and its not the case of lets just apply and do no prep, my dc is bright enough to get in. The exam covers things your dc would not have covered by the time he sits the exam if he is in a state school. If he does not want to go to private, I would not push it. And if your second dc does want to go and do the prep work, then let him. I gave my dc the option to decide if they want to put in the prep work or not. No point in applying if you do not prep, as the exams are very difficult (even for some adults!!). Private school is well worth it if they love doing all the extra sport and clubs they have to offer. My dd just started and she absolutely LOVES it. She wants to do everything and opts to leave for school at 6:50am so she can do the extra morning activities (she also likes to do the lunch time stuff)....basically getting the most out of it. She knew this is what she wanted and was motivated to prep after looking at the websites of the private schools. My ds is the same. If they were not keen, I would not force them.

My brother went private from 7, I went state. Where I grew up the local independent schools were single sex and parents tried to tempt me with the girls school at 11 but I wanted to go where my friends went, to the local comp. I went on to get all A*/A gcses and As at A level, grade 8 in 2 instruments, wasn't sporty at all 😜
I did struggle a bit with confidence at uni and for job interviews for graduate jobs and had feedback about being "sweet but too meek" etc. I have a good job now but I do wonder if I would have built more confidence at independent school.
My brother always had a posher accent (he makes the joke that he didn't have any friends to pick a local accent up from whereas I did) and went on to be a GP.

My DD8 (only one) is confident and sociable, hasn't shown herself to be particularly academic, is sportier than I was and has a lot of hobbies. She does find it hard to concentrate at school (or anywhere) so I think the local independent option may suit her best, but she is already telling me she wants to go to the comp, which is a decent enough one I just worry in big classes she won't progress as well as others. We will see nearer the time but will visit different schools.

I know this doesn't really answer your question but just be aware your DC are too young to make an informed decision. They only have experience of 1 school and 1set of friends.
Whilst you should take their opinion into consideration it should ultimately be your decision.
And you MAY be in the situation in future where your DC ask why you let them make that decision at such a young age, if they feel 1 child got opportunities the other didn't

We sent DS1 private and DS2 to state. Basically we chose the right school for each of them based on a number of factors. DS1 got an academy scholarship that DS2 would never have got and we couldn’t afford to pay without it. DS2 went to comp within walking distance of the house, loved it and had a great local group of friends. DS1’s friendship group was from a much wider geography which was an added difficulty to a long-ish commute.
Despite his academic ability and doing well at school, DS1 got a rubbish degree, where DS2 got rubbish GCSEs and Alevels, took a First at uni and is now doing a Masters.
Try to play the long game and focus on their individual needs- that’s what’s fair, not how much money you spend.