Is the name Dashley ever used??
My little sister named her twin dolls [name]Ashley[/name] and Dashley and I wondered if the name Dashley is an actual name!
(By the way, [name]Ashley[/name] and Dashley have a new baby sister named Cashley…)
Haha, thought I should share…
Dasher - Dashing - Mrs. [name]Dash[/name]
Dashley almost sounds like dastardly, which means “Cowardly and malicious; base.”
I’m definitely not a fan. 
Sorry.
Um, I’m pretty sure she made it up … although, apparently [name]Dashiell[/name] is a real name.
I’d definitely put it in the camp of invented/yooneek names. It sounds like your little sister is a creative little girl who’s simply on a roll with rhyming [name]Ashley[/name] names.