As a parent of one child, my concern for the climate and environment has not waned. However, perhaps my action has, hopefully temporarily, decreased.
Prior to the baby, I had quit a job in medicine to pursue a career in natural resources to at least feel like I was attempting to make a difference. This got put on hold in order to care for our child, and my remaining free time is not usually spent working/volunteering outdoors, calling reps (lol, it's Texas), etc.
Once the little one (or two, my max), are fully into daycare/school, I hope to make my way back into that sphere, whether it be on an employed or volunteer basis.
So I think having young kids especially can shift priorities inward for a time. I hope in my case this is short-lived, and perhaps allows me some time to zero in on the most productive/efficient way to be actionable on climate, while being present and a positive example for my child.
It would really help if local/state/federal governments put more of a priority on this shit. It may be a great opportunity to break into the job market for a lot of careers, but it's pretty fucking difficult to do so for something that actually matters.