I love the name [name]Aria[/name] but he loves the name [name]Amelia[/name] because of the nickname [name]Mia[/name], however if her name is [name]Aria[/name] [name]Madeleine[/name], could we still use the nickname [name]Mia[/name] or is it just too out there?
I don’t think it’s out there. There are many people who give nicknames using a person’s middle name.
Personally I think [name]Aria[/name] [name]Madeleine[/name] is too pretty for a nickname. 
However, it’s all up to you. My nn is an established name in its own right and doesn’t have much in common with my actual name, and very few people have asked about how that has come about. Most people just accept that my nn is my nn, even if it’s not a straightforward shortening of my actual name if that makes sense. Good luck!
I don’t see it personally. [name]Madeleine[/name] [name]Aria[/name] NN [name]Mia[/name] could work I suppose but the sounds are just too out of order in [name]Aria[/name] [name]Madeleine[/name]. What about just naming her [name]Mia[/name]? Or [name]Maria[/name] NN [name]Mia[/name]! I think you could use [name]Mia[/name] and [name]Aria[/name] as a NN for [name]Maria[/name] 
I feel like [name]Aria[/name] is too short and sweet for a nn. If he’s so dead set on the nickname [name]Mia[/name], he can always call her that and make it his special name for her?..
It doesn’t make sense to me at all, sorry.
That said, nicknames don’t have to make sense, so call her what you want! We call my baby a nickname of her middle name, I am sure it confuses the heck out of people that only know what her first name is. So just don’t expect people to understand how you are getting [name]Mia[/name] from [name]Aria[/name] But I am also with laoidh, [name]Aria[/name] is too pretty for a nickname, and is short and sweet enough not to need one, either!
I get it and I think its absolutely fine! In fact, I think [name]Aria[/name] [name]Madeleine[/name] is gorgeous. Goodluck!
I think it’s way too far-fetched.
I knew of a [name]Michaela[/name] nn [name]Mia[/name], but that works imo. [name]Aria[/name] nn [name]Mia[/name] cause her middle name starts with M? That’s just so disconnected imo.
My thoughts as well.
I also agree with stephanie413 about [name]Aria[/name] with a nickname. [name]Aria[/name]'s short enough that it doesn’t need a nickname.
[name]Aria[/name] [name]Madeline[/name] is very pretty, nicknames are just that… nicknames! In my opinion they can be anything that you like, if you want to use [name]Mia[/name] go for it!
Hmmm…
I understand what you’re trying to achieve and I can sort of see how [name]Aria[/name] [name]Madeleine[/name] could make the nickname [name]Mia[/name] in a very vague way. Despite this for me, it doesn’t work. [name]Aria[/name] is a short Italian name similarly to [name]Mia[/name] and is used as a nickname similarly to [name]Mia[/name]. I think using [name]Mia[/name] as a nickname for [name]Aria[/name] is just strange. Especially as middle names aren’t used that often. [name]Do[/name] you like [name]Mia[/name]? As a name in her own right! If so that could make a great compromise using [name]Mia[/name] as her first name, [name]Mia[/name] [name]Madeleine[/name] potentially works? Or you could save [name]Mia[/name] for a potential second daughter and use [name]Aria[/name] [name]Madeleine[/name] which is a pretty combination especially when your partner only loves [name]Amelia[/name] because of the nickname she may never be referred to as [name]Mia[/name] when she starts school and be referred to as [name]Amelia[/name] only!! As the mother you have the final say (in my eyes) use your favourite combination.
xxx
Ditto for me.
Personally, I much prefer [name]Aria[/name] to [name]Mia[/name].
You can call her whatever you want, you can even call her taylor as a nickname, but do I see [name]Mia[/name] in her name? No. It’s definitely not in there, doesn’t make sense to me.