Just curious as to why you think that. To be honest I’m not too bothered about how their names sound together as they’re individual people, as long as it it’s too much of a mouthful as I will probably be saying them together a lot.
I think they are too similar with the een sound in the first syllable of each. Of course they are individual people but you are quite likely to be addressing both children quite frequently. I also think they might be difficult to distinguish when heard from a distance/less distinctly (eg calling one child from downstairs while both upstairs, in the playground where it is noisy, etc).