Firstly, many condolences for your mother and I'm sorry to hear of your loss. My best suggestion to you is to take a look at as many tattoo designs as you can possibly get a hold of. And I mean actual photographs, flash designs, artist portfolios etc.
I always find it a bit odd that people would look for suggestions from others who don't particularly know a lick about them or what their life experiences, morals, values, beliefs may be. We would love to help you, but it's a bit ridiculous with this broad a question.
You know what's best, so don't be lazy.
Check out all the wonderful art there is out there on your own. Develop your own opinions of what designs you like most, and what you know you certainly would not get. In the end you may even find that you're crowding it with too much and want the rose/s only.
Enjoy.