Just to add...
My boy Chad (Shetland) came as a tup lamb and stayed with the flock throughout. He was never any bother, not even at feeds. (They're primitive types, so feeding an all-stock mix, safe for him, was fine.). I didn't at that point have any ewe lambs I didn't want tupped, so they just all stayed together right through until tupping time the following year, when I removed the ewe lambs.
My experience of leaving ewe hoggs with the mothers at lambing time is it's the ewe hoggs who are dangerous! Giddy and silly, and can cause accidents. Now I prefer to let them back together once the lambs are a few days old. The ewe hoggs still get used to lambs and will know what they are when they have their own, but aren't a danger to the newborns or themselves.
When I moved here, we wanted to delay lambing until April, so Chad was kept separate with the wethers until he was needed. Despite these boys being flockmates, and including an older wether, not just hoggs, Chad couldn't settle. He was two fields away from the girls, couldn't see them, but he paced constantly. Every time he saw me, he ran up to the fence looking meaningfully at me.
After tupping (we had left him with the girls for quite a long time) we put him back with the wethers. He was going to have to go now as that was his third crop, but we wanted to put some condition back on him and get past any possibility of ram taint. However, he still couldn't settle. He wasn't going to put any condition on pacing all the time, and he wasn't happy, so after a couple of weeks we decided to send him straight off.
In case it was tainted, we had it all minced, and labelled it 'ram'. If it was tainted, we'd use it for the dogs. However, it was wonderful, and we ate it all ourselves.