addressing 'teenagers' when parents are also invited

we aren't having any kids b/c there are 36 on jusy MY DAD'S side of the family..forget everyone else
but we did want to invite 15 and older....how do we word it

Mr & Mrs J Doe
& Mary Doe

what if they have 2 girls we are inviting?

give the girls one seperate invite..or put on with their parents??

Mr & Mrs. J Doe
Mary & Susan Doe

I'm lost?

FH says stick the one with two girls on one invite...but my one cousin is 17 and on the response card we put ' we have resever ___ seats in your honor...so they will know its just her adn her sister if both their names are on the envelope..

plus my cousin has 6 kids...and she is the'news spreader' in the family, so if she sees i gave just her gilrs an invtie..she'll make sure everyone knows NO KIDDOS

We wrote the parents name on the ourisde enevelope

mr & mrs. smith

and then on the inside envelope wrote the names of who is invited

John - Mary - Jessica - David

Your getting married the day after me, when are you sending out your invites??

i was thinking first week in August

i still have to finish them
and find envelopes