MDM requested additional feedback on this thread.
The claim in the OP looks correct, assuming that (1) the child dependent can be said to be an "individual who has family coverage under a ... health plan", and (2) all other requirements of 26 USC § 223 are satisfied.
This reply is admittedly a bit vacuous because my requirement (2) ensures that no matter what the OP actually said, my statement is true. For what it's worth, I'm not the only one to write stuff like this. The Supreme Court of California has also been known to use this linguistic device. See, e.g.,
In Re Garcia,
58 Cal4th 440, 457 (CA Sup Ct 2014) (explaining that a state law satisfies a test set out in a named federal statute if the state law meets certain specifically mentioned requirements and also "otherwise satisfies the requirements" of the federal statute -- very informative indeed). The reason I went with that language here is that, otherwise, I would have to repeat most of the statute.