Thanks everyone for the insights on first/second instruments and strings/other instruments. I should probably have explained that I’m comparing DD starting flute in spring 2018 with DS starting cello in spring 2022, not one child playing two instruments!
Poor DS, then a little chap of 6.5yo, had actually started trombone at school in autumn 2020, gamely continuing via Zoom January - March 2021 during the second lockdown, and face-to-face for the rest of the school year. However, after one lesson at the beginning of autumn term 2021, the headteacher picked a fight with the long-standing peripatetic brass teacher (and his wife, who’d taught DD flute until she moved up to secondary, and I think also the violin teacher) over room hire charges and that was that, no more trombone at school. It was all very odd and very unfair on all the DC preparing for spring exams. One had the distinct impression that the stress of the pandemic had left the headteacher rather tired and emotional; it wasn’t entirely surprising that he retired this Christmas!
So, yes, cello at school for DS now. I think he’d like to add trombone back at some point but he’s very enthusiastic about cello and likes the teacher. And he’s keeping it bass clef, which is handy.
Still no news on DD’s G5 flute result. I suspect she may be thinking of giving up because of the theory requirement to progress to G6 and because, as a child who works hard but isn’t especially musically gifted, she has other priorities. It would be a pity, not least because she enjoys ensemble playing, but we shall see.