Oak tree sapling? Or not?

I found this in one of my beds, and am hopeful it's an oak tree. If so I am going to transplant it to the yard and nurture it. If it is an oak, can you tell what kind by this picture?

I'm baffled -- my mom, who gardens like her life depends on it, says it isn't an oak tree. But if it's not an oak tree, what else could it possibly be?

Thanks in advance.

 

I think it's a mulberry (Morus sp.) ...

 

I'd concur - Morus of some sort. They're so nifty looking when they're saplings.

 

It's definitely not an oak.

If it's not a mulberry, it might possibly be a hawthorn.

 

White Mulberry Morus alba.

A weed in your area.