Only under the supervision of a medical practitioner.
15 years old. 6 years + 9 years = 15 years. 15 duh
If it's okay with the six year old's parents and the twelve year old is responsible enough than it's probably fine. If you're talking about is it okay legally, than the answer is yes, it's entirely...
I suppose 11, 12 years would do the trick.
I think that is nearly impossible,but...um...idk!! I knew a 12 yr old female in toledo, oh that had a 3 yr old son ....
It depends on who the six year old is. The average height of a six year old is maybe around three feet or maybe a little bit more.