My husband's eldest is about to finish his degree (has been studying in another city) and is talking about moving back to our city. Youngest is here 3 nights a week. Eldest is now 21 and I don't really want to get into the habit of splitting his time between houses again as it feels like I'll effectively have a grown man staying here and expecting to have everything done for him (he did nothing when he lived with us part time before). Plus we don't really have room for him any more.
He has a room at his mum's house across town and obviously DH would still see him, but I think he wants him to become a bit more independent.
What's the norm for adult stepkids in terms of contact time - do they continue splitting their time between houses? For how long?