I know very few who actually use family for childcare - it's a combination of school and afterschool clubs during terms, and holiday clubs, holidays, and some extra leave in summer. And that includes into teenage years - a 10-15 year old who can let themselves in late in the afternoon, make a snack, get changed, start homework/relax watching tv etc, can be a very different prospect to that age having to mind themselves all day every day in summer.
And that latter is the current prospect.
DD still needs "stuff" to do all summer, she is incapable of just unwinding herself at home for more than about 2 days. There are constant phonecalls of "I'm bored, what can I do, what can I eat, when will you be home" and then the phonecalls of "I was so bored I came into town on the bus/train to meet you, when are you finished?". So I put her into various sports camps for most of the summer after an initial week to recover from exams and with a final week to rest and prepare for school. (She gets 11 weeks off!).
The ONLY good thing at present is that, even though she's getting summer holidays in 3 weeks, I am still WFH and potentially until December according to weekend news reports, and DH is also still WFH for a while yet. He will only go as far as the local office once things start back in the office (2km away, not into city), although I will have to go into the city at times to get a certain project done.
But we have been WFH since this started and as busy as ever (DH more so as he spends all day on the phone, and then tries to get his actual work done in the evenings). So we haven't had the relative peace to deal with DD or to unwind that many others have.