Shocked at how birth can age a mother

So, of course, after reading through this sub for years, I've heard plenty of time about how birthing can age the mother's body tremendiously. Yet, a while back I met a distant cousin whom I haven't seen in a long time. She had a baby a year ago. And i kid you not, she (32) looks many years older than her older sister (36). I was geniously shocked when I saw her at first. And I feel sad for her. Less so b/c she looks older, but because it shows what pregnancy and raising a toddler has done to her body. I just hope she actually is as happy as she seems and doesn't suffer from it.