You need a heart to heart with your mum, being a girl she would have had this prob. and by doing this mom feels she's doing her job as your parent, and you are able to ask her anything, plus her opinion is needed and wanted. Don't forget to tell her she a cool mom.
or
Get your grand parents in on this discussion then you have a better knowledge base to make your decision.
As mentioned a family do would cover it, preferably a day time BBQ, where all are casually dressed and men are around the BBQ hot plate discussing blokey things. He then can be a member of the Beer and BBQ club. Now you've lost him to the world that is bromance.......oh well now you'll have to kidnap him and do testosterone detox.