Should I tell him what she says?!?

[Christi Mcdonald]

okay well my best friend moved from a diffrent state and her ex is still there which they still really like eachother they only broke up cause of distance. well theyve gotten really close this summer and him and I have talked a few times like through Facebook commenting on her status and then he dm'd me on twitter asking me to keep her away from all the other dudes at school this year (jokingly but serious) I know that most of you will say it's like puppy love or something but honestly both of us don't believe you can be in live at our age and were both very picky about guys so were not some 13 year old girls that date every guy. anyway he dm'd me for my number cause he had to ask me something about her so he called me and asked what was wrong with her & I haven't talked to her today so I texted her and she said she tell me when she saw me in person and it wasn't a big deal so she's comin over tomorrow and I wanna know if I should tell him or not depending on what it is?