Parenting 4 Kids Nationally accredited, 4 Kids Early Learning Network serves children and families throughout the Mon Valley. Through this column, 4 Kids staff members answer reader questions about raising children in the critical early years. E-mail questions for consideration to: questions@4kidsearlyed.org, or mail to: 4 Kids Questions, 445 Fourth St., Braddock, PA 15104.

Q: I have a beautiful 12-month-old granddaughter. Her parents are "health nuts," which in some ways is good because they're very careful about exercise and diet. But they are totally paranoid about the baby having any sugar or fat in her diet, and she is so tiny -- just the 4th percentile! Is this a good thing, or do they need to lighten up?

A: Our expertise is more in children's overall development than in pediatric health issues like this. We're also unaware of your granddaughter's medical history. Just for clarification, we need to ask whether you are certain that she is in just the 4th percentile?

If so, at 12 months, she would weigh approximately 17 pounds; the average weight should be about 21 pounds. If this is the case, we are profoundly concerned, and we feel the situation requires the immediate advice of medical professionals.

The average full-term baby should double his or her birthweight by 4 months, and triple it by 12 months. We're wondering if your granddaughter has done that. Pediatricians plot each child's height and weight on a percentile chart to track whether progress is appropriate, and to watch for early signs of failure to thrive. Height and weight percentiles should be similar to each other. Are your granddaughter's?

Do this baby's parents take her to all the recommended well-child appointments? Has the doctor mentioned and monitored this very concerning issue?

Another thing to consider: Are the baby's parents vegans? Experts say that vegan babies generally gain weight more slowly than other babies, but that any vegan child under the 5th percentile is extreme, and should be seen immediately by the pediatrician.

Please urge your granddaughter's parents to take the baby to the pediatrician right now for a thorough checkup and an in-depth discussion of child nutrition. If the parents refuse to follow up on this with the pediatrician, you must call the local child protection agency.