At a casual concert at the Stewart house, 10-year-old Maggie is practicing her tunes for an upcoming piano recital.
Her little sister, 8-year-old May, listens attentively with a doll that she made by hand.
Wendy and Todd Stewart say both girls were babies when they were adopted from China. Maggie was first, adopted when Wendy was 42 and Todd was 39.
May was adopted two years later. She plays violin.
The Stewarts feel the girls have some advantage in having older parents.
"When you were younger, you were more worried about going out and doing things, and we've done all that, so you know, we just concentrate on them," said Todd.
"We got that part out of our systems," Wendy added.
A study at the University of Virginia shows that children of older moms score higher than other kids in math and reading tests. And for every year older the first-time mother is, the scores go higher.
Also, kids can help their older parents be more active.
A 2005 study showed that older moms may have had problems during pregnancy, but ended up living longer than women who are not raising children late in life.
Older parents tend to practice healthier lifestyles in order to care for their kids. Todd and Wendy say their girls keep them active – Todd is even their soccer coach.
Gisele Haralson's little boy Gavin is a bundle of energy. Gisele was 39 when he was born.
After years of trying to have children, Haralson's son arrived when Gisele had already achieved a lot on the career front.
"When I was younger, I was really focused on my career. I was focused on just getting out there and conquering life," she said. "But at this stage in my life, I'm settled. I'm comfortable in myself. I'm very in tune to what it is that he needs."
University of Houston Sociologist Elizabeth Gregory says one in every seven children born is born to a mother 35 or older. That's four times the number of children born to older moms only a generation ago.
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