Is anyone worried about being lonely as an old person?

I am OAD not by choice as my wife only wants one. I respect her decision and her reasons why and I am working on coming to peace with this reality and seeing all the positives of being OAD (side note: reading the experiences of folks here has been really useful and reassuring for this — thank you all).

I still come back to a fear that admittedly may be selfish, but still something that I think about. What if something happens to my wife and/or daughter and there’s no one there to help me at the end of my life? I have been blessed to have 2 grandparents still alive in their nineties, and as they approach end of life they are surrounded by multiple grown children and lots of grandchildren. I can’t help but imagine what life would look like for me, and worry about a world where I have no one to be with me. And it’s this image that keeps me thinking about more kids. I feel like I need someone to talk some sense in me that I shouldn’t be worrying (or even catastrophizing) about this.

So here’s my question to the group. Do other OAD parents ever worry that only having one kid could lead to being more lonely in old age? Why or why not?

Thank you all for your thoughts — appreciate this space and this group.

EDIT: thank you for the thoughtful responses everyone. I really appreciate it.