I agree i think its a bit much to ask an 18yr old to share a room.Yes they are old enough to understand the needs of others but so are we and quite frankly an 18yr and a teen need more privacy than a baby.

We have a sim thing here we have 5yrs between the two boys and expecting one in Jan. We only have a 3bed home too. But i decided theres no way im going to make the older two share. We have sucked it up and know we need to move.So in time we will.But mine are also younger than yours lol