Accidents happen. A Mooresville, N.C., family is grappling with that fact after a lawnmower accident severely injured their 4-year-old son in late April.

The little boy is requiring complex medical attention from a variety of specialists.

About 210,000 people, 16,000 of them children under age 19, were treated in doctors' offices, clinics and emergency rooms for lawnmower-related injuries in 2007, according to the U.S. Consumer Product Safety Commission.

To help prevent injuries, a team of surgeons and the American Academy of Pediatrics teamed up to educate parents, adults and children about the importance of lawnmower safety. Their tips include:

--Children should be at least 12 before they operate any lawnmower, and at least 16 for a ride-on mower.

--Children should never be passengers on ride-on mowers.

--Before mowing, pick up stones, toys and debris from the lawn to prevent injuries from flying objects.

The safest place for a child to be is inside while an adult is mowing. Little kids lack impulse control and cannot be counted on to stay put in a certain part of the yard, for example.

When parents and caregivers understand the abilities of children at various stages of development, they've taken the first step to being able to prevent serious injuries, says Dr. Martin Eichelberger, founder of Safe Kids Worldwide and former chief of Trauma and Burn Services, Children's National Medical Center in Washington, D.C.

A study of child development and unintentional injury released by Safe Kids USA, "Raising Safe Kids: One Stage at a Time," links age-appropriate safety tips to research on children's cognitive, behavioral and physical development.

"Your child's physical, behavioral and cognitive abilities should affect the precautions you take to help them avoid serious injury," says Eichelberger.

Limitations and tips by age group, from the report, include:

--Infants have spines that are not fully developed, leaving them vulnerable to injury if they are not correctly positioned in a rear-facing car seat. They have a slower digestion rate and a lower tolerance for medication. Their skin is thinner and more sensitive, meaning it can burn more quickly than that of an adult. Take special care to follow directions so you don't overmedicate your baby. Don't tote your baby on your hip while you're cooking.

--Children ages 1-4 have muscles and bones that are not fully developed. They are still learning how to balance themselves and adjust their stance to avoid falls. They may wander off unsupervised. Choose childproof medicines and store house cleaners out of reach. Give them safe places to play and soft tumbling spots.

--Children ages 5-9 have trouble recognizing and avoiding obstacles and lack an adult's hand-eye coordination. Make sure children wear a helmet and protective gear every time they are on wheels. Keep children in booster seats with the vehicle lap and shoulder safety belts until the seat belt fits correctly.

--Early adolescents have less defined visual perception than older teens and lack the ability to recognize a specific object from within a busy background. This is an important skill used to identify oncoming cars in busy intersections. Make sure your child wears a helmet and protective gear every time he or she is on a bike, scooter, skateboard or inline skates.

Can you help?

Q: My daughter had her first baby in January, and after a monthlong stay in the hospital, the baby came home under the watchful eye of her parents. How does she now get the baby to sleep in the crib, since she has been in the cradle next to their bed, since she came home? The cradle does swing at the beginning, but only for a short time, and my granddaughter sleeps well. But now my daughter is trying to put her down in the crib when she falls asleep, and my granddaughter doesn't seem to like that and wakes up. Any suggestions or books will be greatly appreciated. — a grandmother in Texas.