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.
yes
No.
A thirteen year old girl can get pregnant if she has started ovulating and has unprotected sex.
yes.
25 or 13 or 81, age difference is not a factor in getting pregnant.
Yes
if you are asking can you get pregnant by self masturbation the answer is NO
A 13-year-old boy absolutely CAN impregnate a girl. Use condoms!
Generally it is illegal to rape a 12 or 13 year old.
No as long as both parents are ok with it and you use a condom
Yes they can. Many 12 and 13 year olds have been pregnant and have given birth to children.