This week McClean's best friend Eugene Ferry, a back-up goalkeeper from Derry City, announced he will be going over to the North East to stay with McClean and ensure he stays clear of trouble.
O'Neill said: "I don't even know who James' best friend is. I'm delighted he has one and he did mention that there was someone going to come over. I've not got a problem with that and it's not a big issue. He's not five years of age although I've said to you he's 23 going on it!
"I just think he's been a little bit homesick, that's my thought. James might not go with that. Lots of things have happened to him and my annoyance with him was purely on the Tweeting aspect more than anything else, especially some of the choice language and picking Trapattoni's team for him.
"There's a difference to telling James to be a bit sensible but I don't think he's gone off the rails or anything. My concern is him playing well for us. If there's something off the field, then on a serious note I have to look at that. If he's happy with someone living with him then fine."