I empathise. I have two GDs, 12 and 13, and from the moment they were born I was very involved (my daughter was a single mother, and wanted/ needed the help). My partner and I had both girls to stay for extended periods, from birth until they started school, at which point we had them most weekends and holidays. I'd carry them around, play with them, be up at night with them. All with relatively little difficulty. I now have a 1 year old GS and my daughter isn't happy that I'm not as involved with him, but I just can't do it these days. I can't carry him for more than a couple of minutes, and am totally exhausted if I babysit for even a couple of hours, and it takes me a couple of days to recover. DD doesn't seem to understand that I'm over a decade older than I was when she had her girls. I'm only 62, but I've had a chronic pain and fatigue condition for over 20 years. I managed in my 50's, but I'm wrecked now. I love him to bits, but I can't have him overnight on my own, not least because I worry that I'd drop him! My partner and I don't live together (we used to, but we're both neurodivergent and quickly discovered we're better with our own space), and so I'll go and stay with her for a couple of nights and we'll have GS then, so we can look after him between us. DD is constantly trying to guilt me into having him on my own, but I can't (she actually asked me why I "won't" have him. When I said it's "can't" not "won't", she asked what the difference was!). I'd love to be more able, because he's an absolute joy, but it is what it is. Aging sucks!