I love your kids names! They are full of meaning and have lovely sounds. I think adding the accent makes the pronunciation more clear ( I would never call Sélah See-lah, if anything it would sound more like “Seh-lah” which is much closer, but [name_f]Selah[/name_f] without the accent I think I would be more likely to say See-lah.) While I don’t think that it’s absolutely necessary, and I can see where other commenters are coming from about it not being [name_m]French[/name_m] and whatnot, I don’t think that outweighs the benefits- it helps you express how you would like it pronounced, and it gives her a special connection to her sister (so sweet and unique!) I say go for it, it’s not like you haven’t done your research or you’re trying to name your kid Myddlynn (pronounced Mad-uh-line)
I’ve always read it as [name_m]Say[/name_m]-luh.
I’ve only known one [name_f]Sela[/name_f] (spelled without the h) and she pronounced it See-LUH, emphasis on the last syllable. She was South African, if you wanted to know. But I know that most people who bring up the name [name_f]Selah[/name_f] say it [name_m]SAY[/name_m]-luh.
In your case, therefore, I’m inclined to agree with the posters who say that the accent is both unnecessary and used incorrectly. You mention that it seems to be a personal matter, but if I were you, I’d go back and read the posts, because most of them deal with the question from a linguistic, factual point of view, not a preference. I am not an expert in [name_m]French[/name_m], but I understand that the accent on the e makes the eh sound, not ay, unless the e is at the end of the word. Therefore, I think with the accent, the name would be pronounced sell-uh. I would leave the accent off if it were me, because it seems that the pronunciation would be more confusing if it was included. [name_m]Trust[/name_m] that you’ve got enough connections between the sisters…how about including their brother a little more? [name_m]Just[/name_m] a thought…
I love Selah! And I like the accent also to match your other daughters name. I’ve always said See-luh but I prefer Say-luh. How do you pronounce your daughter’s name? Is it am-uh-ray like “I am”? Or ama-ray like the last part of mama? I’ve never seen it before and it’s not on nameberry. Its very pretty!
We pronounce Amaré just as you would say “I am a ray of sunshine.” 
Thanks! Yes, it’s Latin, and the accent and emphasis were our own. It clearly upsets many people, lol. I don’t really mind, as she likes it, and it’s grammatically correct.
Thanks for your kind words.
Again, thanks for all the input.
It can certainly be an experience to ask for people’s opinions on Nameberry.
I wrote an article for NB once about my son’s name, [name_m]Job[/name_m]. [name_m]Trust[/name_m] me–I’m getting used to people’s opinions, solicited and not. When I look at names researched, heralded, and loved on Nameberry, though, I think spelling and pronunciation all come down to personal opinion.
As far as looking into detail about what people claim on the accents… I see a lot of input from those who have studied [name_m]French[/name_m] (not so much native-[name_m]French[/name_m]-speakers), but I was never claiming for this to be a [name_m]French[/name_m] word, I was just wondering if it would produce more of an “ay” sound in most readers, naturally, like the accent agui does in Beyoncé.
I will make a decision accordingly. [name_u]Truth[/name_u] be told, people are OFTEN thrown off by my name, simply because it’s spelled “[name_f]Rebekah[/name_f]”-- and that is not exactly a far-out spelling. 
It was great to hear all the input, no matter what.
thank you all!
Ha thanks. Yes, not trying to have a super-far out spelling. [name_m]Just[/name_m] one accent that people can leave off by accident and it won’t necessarily hurt anything. 
Thanks for your input! I have definitely read through the posts several times. The factual point of view is still up for grabs, though, and I will continue to research; I see a lot of people who have studied French but are not perhaps experts in this area. It would be great to ask a native-speaker, although, honestly, I’m not trying to create a French name. I was just wondering if it would produce the same effect in people’s initial views on pronouncing it.
In terms of the accent making the “eh” sound, I have seen it both ways in the factual response, both here and on the other post I put. The grave accent would seem to get much more of a “eh” sound, if we are going solely by French, at least according to the commentary. But again, I’m not bent on this being a French name. So…back to the drawing board on that one, for me.
Their brother’s name is meant to be set apart, as we’re naming our girls more whimsical, soft names that involve love, and went for a stronger, boyish name tied with a legacy of faithfulness… if we had had a boy, we had a name to match his. Yes, I don’t have the matchy sib-sets, but to be honest, we just pick the names we care about and love.
Thanks again!
thanks for your input!
Good to know! Thank you.
Ha! Yes, it does sound a lot like [name_u]Sailor[/name_u], especially said quickly. Thank you!
Good to know. thanks!
Thanks! No, it’s very helpful. Most people think the accent is unnecessary, some are certain it’s wrong, some say it’s right…but the greatest news of all is that it seems most people think to say “[name_m]SAY[/name_m]-luh” right away, rather than SEE-luh. That was the biggest (pleasant) surprise to me. Thanks for your input!
thanks!