My niece just found out that she is pregnant ..nw she is 7 weeks pregnant. she said she had ?

on the 4th oct with her new b/f and claimed that he s a lil by accident while doing withdrawal..she washed it away and that was it. She is only 1 mth in relationship with her new b/f....but before this 4th oct, she had one while she was with her ex b/f. so who is the father of the child? whose do you tink it is? please comment.. she's only 19.. =( now thinking of aborting.. which i totally disagree..