Question on addressing guests on envelopes...

for some reason I am having such a hard time with this for example, if I invite an aunt, uncle and cousin do I address them as...

Mr. & Mrs. _____ _____ & Family?

(or)

Mr. & Mrs. _____ _____ & cousin's name

Is there a website that gives you pointers with this?

Please help, TIA

'Invited With Kids
Names of children under 18 years old need not appear on the outer envelope, but over-18ers who live at home should either appear on their parents' envelope or, preferably, be sent their own invitation.
Mr. and Mrs. Ebert Estonia
& Farrah Estonia
195 Oak Boulevard
Chicago, Illinois 51515'

linky

Thank you so much, this information is SO helpful!!