OYBK, my mum was so, so proud of DC1 going off to university. I'm surprised she didn't take a full page as in the local paper! But she is proud of all her GCs - they are all very different to each other and each successful in different ways. MIL? Her reaction was to tell Dh that her youngest gc had learned to ride a bike. Which is lovely, but she just could not, And still cannot, acknowledge anything Dh and my dcs go as anything other than a very poor second place behind whatever her other GCs have done. That's fine. It just means that now, neither DC tells her about any of their achievements and, both of them have so e very special achievements that would make most people very, very proud. Dc1's academia achievements and what he has achieved so far on his career, are truly amazing. But MIL doesn't even know about most of them. At dc1s insistence. As you say, grandparents reap what they sow and now that all her other GCs are not around as much as they used to be, she can't understand why my dcs are not rushing to spend tine with her.
Anyway, what I really wanted to say was that when we took dc1 to university, we arrived home to find a letter to each of us, thanking us for our support with studies and sorting out the practical side of going to uni. There was also a lovely letter for dc2, full of encouragement for their studies at sixth form. The letters were typical of dc1 - sincere, thoughtful and funny. I can tell you, the three of us left at home had a few years that night. I still have my letter and it can still bring me to tears. I hope your dcs all find a way to show their appreciation of all your support, even if it takes a while, they really will realise how lucky they've been to have such supportive parents.