Whatever stage of life you're in, a ranch home will suit your needs with a young family and as you age.
Ranches make it easier to tend to small children during the night and for keeping a watchful eye on them during the day. No stairs means fewer chances for falls.
Fab 40s &50s
Though you are still active and spry, you're likely reaching the age where your folks could use a bit of assistance. Keeping things on one level allows you to safely take them in with ease, while giving you flexibility for your own needs.
Obviously, as we age mobility becomes more of a factor. If you plan ahead with smart single-level design and strategic ADA considerations, a ranch can be the foundation to allow you to remain in your home for good.