Sweet potato related to morning glory

Okay, here is how I got confused. Ipomoea is sweet potato (Ipomoea batatas) and morning glory (Ipomoea tricolor). I know you are not supposed to eat the morning glories. However, a call to poison control a few years back reassured me that Logan(8 years of age) and Rhonda (39 years of age) would not die from eating the flowers, but they could have visions from eating a lot of the seeds (I didn't share that part with them). When Logan tasted Datura we had a problem, that is poisonous and he had a numb mouth for a while. Turns out he spit it out when it didn't taste like the morning glories.

Not poisonous

My lovely sister decided to eat the tuber of an ornamental sweet potato vine (Ipomoea). No she is not three. I was afraid it was poisonous, not so. You may eat it if you like. It doesn't look quite right though, kind of whitish instead of orange. She said it tasted good. I'll take her word for it. Seems like my b-i-l said his websearch showed that it was actually related to regular sweet potatos.