Having a baby in my 40s was hard. But I was able to appreciate little things more.

The author chose to have a fourth child in her 40s.

Courtesy of the author

• I had kids in my 20s, 30s and 40s.
• While my body took longer to recover the older I got, I also learned to enjoy little things more.
• I've learned that there is no "right" age for when to have kids.

Parenting is one of those experiences that somehow gets better and harder with age.

When I had babies in my 20s, I was young and optimistic — I figured I could handle anything. By my 30s...