The review for this song fails to explain that it is about a (possibly old) couple going through a struggle with Mental Illness and discussing their inevitable Death, where they will be together as they once were, when they were young, before the Mental Illness separated them.
It could be Alzheimer's, Dementia, Schizophrenia, or something else that the woman is going through, but she talks about losing grips with reality, and the man is trying to comfort her as he witnesses her slipping away.
"Woman: And some days I can't even trust myself
Man: It's killing me to see you this way"
"Woman: Some days I don't know if I am wrong or right
Man: Your mind is playing tricks on you, my dear"
The man talks about how the woman is too far gone in her mental capacity, and they will "meet again soon" when they've both passed away.
"You're gone, gone, gone away
I watched you disappear
All that's left is the ghost of you.
Now we're torn, torn, torn apart,
There's nothing we can do
Just let me go we'll meet again soon"
And this is a more literal meaning for meeting again in Death:
"'Cause though the truth may vary
This ship will carry our bodies safe to shore"
Younger kids will most likely not understand the meaning of the song. Older ones might question some things. 'Bodies' is the word that stands out to me, since its connotation most likely brings Death to mind.
The song contains no bad words, no violence or sex. If that's all you're looking for, then the song is fine. But the issues of Mental Illness and Death may be sensitive topics for Parents to address.