You are doing a lot ! and to answer your question , there is nothing wrong with you and your husband! I am not on Grandma duty just now due to Covid. I have to say I do not miss the early mornings!! When I was up early for child care I woke feeling overwhelmed with the prospect. I took care of my elder daughters children some years ago - no problem, but I am older now and notice the difference. May I suggest you and your DH have a chat and decide how much ( if any) childcare you can offer - perhaps sleepovers can be stopped? Form a united front and speak to your AC, sometimes our AC forget we are getting older , we are still capable Mum !! Not sure if this is your only GC if so there may be more, so please speak to the childs parents asap, set your boundaries and please stick to them . I am very maternal and always worked with children so it is hard for me to accept my limitations. Go for it , stuck to your guns and only offer what you know you can manage. Good luck.