just for a drink (not a party) do you insist that your teenagers
a) pop in and say Hi, then disappear again
b) pop in, have a drink and then disappear
c) join you all for the duration
d) not show their faces at all - even if they are at home
or
e) your teenagers are out having a better social life than you so it doesn't arise as they are not at home when your guests are round.