I retired just after my GS was born but my DS and DiL were moving abroad so apart from helping with the move I haven't been involved with childcare. They are returning to the UK later this year and I plan to downsize and move nearer so I can be involved, but I've already said I'm not offering regular childcare but would be willing to step in when regular arrangements fall through due to illness or other emergency. I feel that I don't have the energy required to help on a regular (I'm 67 now) and I certainly wouldn't cope with a significant commute - I couldn't have coped with that distance when I worked!
I was a stay at home mum, but still remember how difficult it was to arrange for childcare on occasions for any sort of emergency as I didn't have any family nearby, so I hope what I've offered will be helpful without being too big a commitment for me.
I realise too that once I move nearer I need to build a new life for myself in the new area, make new friends and get involved in new things as there is no guarantee their family will remain where they plan to live in the longer term. If their jobs move them elsewhere I don't want to have to relocate again in order to have a life near them. I'm looking forward to living nearer and being involved, but can't put my whole life on hold to help them, knowing that as my GS gets older I'll no longer be needed.
I'll be moving to a much cheaper area with this move, not so much downsizing as down-pricing, so there are other benefits for me too. I'll be nearer other family and old friends who live in that part of the country, but it will still be a huge uprooting as I've lived where I am now for nearly 20 years.
I feel that I need this to be my last major relocation in my life as big changes get harder to make the older you get.
Whatever you decide I wish you luck, but I realised I need to be realistic about what I'm capable of, and offering to do something then finding it is too much to cope with would probably be a bigger let down than saying no in the first place. Make sure you aren't being pushed into something which is too big an ask!