when...your 20 year old gives you a voluntary hug, for possibly only the 3rd time in his entire life (no joke! Suspected ASD) for spending 6 hours in the car to ferry him somewhere important. 
And is then ridiculously pleased with himself for having "done an egg" for the first time ever - ie cooked himself a fried egg 
He has made a very complex technical Lego model within 24 hours, and regularly takes his actual car to pieces (and puts it back together!) but for some reason, to him, the fried egg was a big achievement!
The lockdown has actually been really lovely in terms of having all the DCs together a bit more and interacting - so many laughs and nice chats.
I think the pinnacle of my pride as a parent was when the three of them went to visit their dad abroad earlier this year. DS1 drove to the airport and then they navigated Heathrow, when all the display boards were down and computers weren't working, with huge delays to their flight. A very stressful time for them all (and for me, hearing about it all from home!) as their first taste of independent travel, but they did it.
And when DD said that she can't moan about me to her friends because they all know I'm the coolest mum and that she's lucky to have me, so even when I make her do jobs and tell her off, nobody sympathises with her when she complains