Question about ashes

Hi all, I have posted here before about the stillbirth of my daughter last year. As we approach the one year anniversary (still a few months to go, but time is quickly moving forward always!). I've been thinking about her ashes. There was so much of her (good bones lol), that we have her small urn and then an extra velvet bag of ashes. We've decided to spread her ashes in a body of water that means a lot to us. When she died I bathed my body in the water and submerged myself completely before her delivery. When I was able to swim after some healing, I returned there with empty arms and an empty belly. The rest of her ashes (in the urn) I've decided I would like to keep with me for the rest of my life. But then it occured to me that when I die, what will become of her ashes?

I plan to be cremated - a cultural rite that my family observes (maybe we'll have open pyre options then? Or the heat from the crematorium will be used to power things?! Wishful thinking...).

And so I thought to myself I'd actually like my daughters ashes to be placed with me during my cremation/open casket viewing. So that I can return to dust and what's left of our bodies can be returned to each other. The urn has metallic components and so I think that she'd have to be transferred to a cloth bag or something similar.

My question is....will my family run into issues by doing this? I guess this is called commingling of ashes and I just wonder if some funeral directors will be sticky about this. Are there things I can do to try and ensure that this happens (perhaps in a last will and testament?). Thanks for helping me think about these death plans!