If she has started her period, and they're having unprotected sex - sure.
It should also be pointed out that this is highly illegal. A 13 year old is way below the legal age of sexual consent and is actually a child. Therefore an older man having sex with a 13 year old is a paedophile who will soon spend the rest of his life behind bars (sharing a shower with a "large" and well-muscled man called Bub).
The 13 year old will also be ordered by the court to attend counselling sessions.
If the fifteen year old is ovulating and the 12 year is producing sperm, yes.
Yes
It is impossible for a year old girl to become pregnant.
No, definitely not. A 16 year old girl is not considered an adult wheather she is pregnant or not!
Yes, an 8 year old can get pregnant. The youngest birth on record was to a 5 year old girl.
a girl can get pregnant at one year old
A thirteen year old girl can get pregnant if she has started ovulating and has unprotected sex.
yes
NO, that is not possible.
No, they cannot because girls cannot get each other pregnant. If you are asking whether a 13 year old can get pregnant by a thirteen year old boy, then the answer is 'yes'. If he is producing sperm and she is producing eggs and they have sex, it is possible for her to get pregnant.
a girl can get pregnant at one year old
Yes, it is possible for a 60-year-old man to get a woman pregnant as long as he is still producing viable sperm. However, the likelihood of conception decreases with age due to lower sperm count and quality. It is advisable for older men to consult with a doctor for advice on fertility.
Yes
Yes.