Love the name Kaden, definitely not a girls name! It sounds adorable!
I would choose Josiah, lovely name!
There are so many Kaden, Caden, Caiden, Kayden and Braden, Hayden and Payden in our elementary school, all those names rhyming with "maiden" got wildly overused about 5 years ago. Josiah sounds better to me.
I think Kaden is nice, never heard a girl called this name