Jealous family

So my since I told my family I was pregnant a while back my little cousin who is only 14 is I think jealous like she's been faking pregnancy symptoms and researching pregnancy and stopped taking her birthcontrol... She's only been with her boyfriend for 2-3 months and I've been with my fiance for 5 years ... Its almost like she's trying to trap him in the relationship but I don't think she understands that not every man is like mine.. Her boyfriend is 15 and he could just walk out on her ... Several of my family members and myself have told talk to both of them about this but she still continues on with her fake pregnancy any advice IK its kinda weird