Tropicals & Tender Perennials: Look-Dark & light green variegated brug, 1 by AuntB

AuntB wrote:
I had seen this limb in one of my brugs for a couple years. (I think I posted, but not much response)...Last year, I snipped it off and rooted it. It stayed variegated green and alive in my basement all winter and here it is now... Still 2 color green variegated... I love it. Why do they do that? How do they do that? I'd expected it to revert, but it hasn't and I don't think it will, now. I've never seen one like it.