You have a kid? 40lbs is NOTHING!!!!
Typically, my wife would herd the kids, and carry their cloths. A big pack but not a lot of weight, diapers, sleepers, winter sleepers, blankets, etc...about 25lb worth for 4 nights.
We did this some. Avery fourth or fifth trip.
I carried everything else. Tent, tarp, stove, fuel, our bags, mats(one extra for the kids,)
food, trail water, ... lots more. 50lb was where I drew the line.
Most of the camping season, we went car camping in parks. Day hikes to fishing holes, around the area, etc. Earlier/later on we would take a short hike (5-7mi) into a small lake. As they grew we went further into the woods. Eventually leaving the parks for the wilderness areas.
About half of our trips were still car camping. Over 100lb of gear: Bikes, toys, two tents...well, I am sure you get the picture. At around age 12-13, They started carrying their own gear, and, their friends. Once, they carried the boat... It made them very proud to think they could do that.
Now days, they are off working, raising their own families. They make it a point to go out with me once per year. The wife doesn't go, she has the grandkids, I take them one at a time for 5-10 days. Significant, because they set it up. They have places they want to see. They want to see critters (last year my daughter saw a moose at 32 years old. My other daughter saw a bear with her cub. Mama bear shoo'ed him up a tree as we paddled by, I sent my camera swimming.)
And we are back to UL weights, now. I carried 25#, my daughter carried about 23# for a ten day trip, for example.
You will find that kids need/want/expect more than an adult. This doesn't change for twenty years. Car camping with kids, is not being an impostor, it is being pragmatic. If I had to choose between the kids and going camping, I would choose the kids. Do Not feel different because you had one. Just do what you can to make both work. Both will work together, somehow. It will work out. Work is the keynote...kids are more work.