"...but it wasn't until she and husband Eric Landon had triplets born at 26 weeks that the nonprofit's mission became personal. Two of the twins, Vivian and Levi, are now healthy 5-year-olds... "

Looks more like poor editing and a lack of detail on the part of the reporter. She calls them triplets, then in the next sentence calls them twins.

I don't think I would correct the reporter in a thank you note. But I would definitely say things like "we enjoyed sharing about our triplets with you" or "thank you for sharing the story about our triplets, E, V, & L, and for helping to promote the MOD".

If you really feel that something should be said more directly, I would consider writing a note to the editor about attention to detail and proper use of the language. "two of the twins" really doesn't make sense.

MonsterMom6
10 year old ^b^ b twins @ 30w5d (1 survivor) and
8 year old gggg quads @ 32w0d