Help advice for my best friend wot I can't answer

Jane
Help my best friend has come to me. But ant give her any advice 
She thinks her son is her ex partners she thought he was around the time she conceived she slept with 2 brothers in few days to a week of each other but she slept with one brother days later she got drunk and he took advantage on her. And she slept with other brother she wasn't in no relationship with eaither of them 
She slept with second brother then around 4 hours later or6 hrs she started to bleed she had her period she didn't see eaither brothers  but month later she didn't have a period and took a test she was pregnant the midwife who scanned her couldn't tell her when baby was conceived this was over 5 yrs ago now she thought it was the younger brother as she already has a child with the older brother now a lot ppl are saying they both look alike and has doubts her youngest is the younger brother who slept with in 6th Aug 2009 
I told her she should had a snap test as soon he was born she said was going to but the guy decided not to as said his son looks like him but too many things looks like his older brother so I haven't a clue wot advice to give her as she said it would help a lot if anyone can give advice iv run out wot to say I do know both boys do look alike first time seen them together since was a baby.
Please can anyone help my friend I know she was silly to go with both brothers .