One of the things I had to get used to when we switched from Korean adoption to Ethiopian adoption was the fact that we would not know our children's actual birthdates. Korea is good about documenting such facts. Not only do I know the dates that our Korean boys were born, I also know the time of day and how much they weighed at birth.
For our Ethiopian children there is no such precision. Some folks do indeed learn exact birthdates. And in the case of kids who came into care as tiny babies, you'll probably get a birthdate estimate that is within a few weeks of correct. But for older kids it is a very inexact guessing game.
The various methods of estimating children's ages include looking at their size, noticing their tooth development, and getting a bone scan done. These ways of assessing kids do give you some idea of the child's age, but none is exact.
Size
Obviously, people come in all sizes and kids grow at different rates. Kids who have lived in tough home circumstances or in orphanages will often grow slowly, and then have a huge burst of growth once home, leaving the parents realizing that the estimated age is (in some cases) several years off.
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Teeth
Tooth development also varies a lot. Among my own biological children, one got a first tooth at 4 months and another was 11 months old before she had even one tooth. Some kids lose their first tooth right at age 5. Some are nearly 7 before they lose one. Though a dentist will be able to give you an estimate of a child's age, depending on the age of the child he'll probably only be able to estimate age within a year or so.
Bone Scan
That leaves the bone scan method of 'aging' a child. This method is fairly pricey and can only give you an estimate within 12-18 months of age. If your child is suspected to be nearing age 16 at homecoming, U.S. Immigration will ask that your child have a bone scan, since legally the only way an immigrant child over 16 can be adopted is if you are also adopting or have already adopted his/her biological siblings.
If you are very uncertain about your child's age, you would probably be wise to see how your child grows and develops once home. You may also be able to make some guesses by motor skills and behavior. But keep in mind that newly adopted kids will often act younger than their actual age for awhile, and will often have some motor delays.
Many people who become convinced that the child's assigned birthdate is inaccurate will use all of the above methods to get a ballpark guesstimate of age. You can then go to your pediatrician with your findings. Your pediatrician should be able to make an age estimate based on all those finding and then write a letter to the court recommending a new birthdate for your child if needed.
Some families feel that making their child 'younger' will be to the child's benefit and give him more time to catch up in school. Others realize that kids need to be made 'older' because they are much larger than other kids close to their original guesstimated age. And since Ethiopians are not large people in general, this can be a fairly good clue that the original birthdate is off.
You can get your child's birthdate legally changed at the same time that you refinalize your adoption in U.S. courts. Most judges will look only at the doctor's letter, but some families report that judges have asked for supporting evidence. You would be wise to bring dental findings and bone scan reports to court with you. Most families report that judges have no problem with setting a new birthdate for the child when the proper documents are provided in court.
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