Faced with the same scenario (wife very interested in doing more bushwalking with me, and we have a 15month old daughter, planning for another), I've ordered a 4 person mid (a 9x9) from oware, in silnylon. Actually, most of my walking will likely be with them from now on. We carry our daughter, but over time she will do more and more walking, but total distances, etc won't ever be as much as when I'm solo, at best maybe 70%. So I didn't have to pick the lightest possible shelter for this (eg cuben) and silnylon is a bit more forgiving (stretchiness, abrasion) with kids inside.
I still have my trailstar if in the future I head out with one of the kids when they are older, or just me and my wife, or we can take the mid.
I'm looking at lighter options for myself. Actually as I won't get many nights per year by myself, I can probably shoot for lighter cuben (eg .3, .51oz) small tarps (will prob make my own), as it will still last a decade or more, and if I'm looking at more extreme weather I can pack the trailstar just for myself.