Even the Financial Samurai went back to work after having a child. I think retiring in one's 30s sounds romantic, but even if one forgoes children, travel, or other expenses, 60 years in "retirement" is just too unpredictable in terms of the expenses that can come up. And, as you point out, having many "zero years" in one's Social Security record extends that uncertainty into the future. I think retiring or going part-time in one's late 50s or early 60s provides the best of both worlds: enough time to build assets and enough time left in retirement - and still healthy enough to enjoy it.