I've got a boy who is about 9. He's got a friend who is touchy-feely. I can't say they're doing anything wrong, but he just sort of hangs from my son a bit much. It makes me uncomfortable.
On the other hand, I'm not touchy feely myself. So maybe it's just a personality difference. Also, I'm a major homophobe (no offense). So maybe I'm just hypersensitive. Is my concern valid?
If they just hold hands, I wouldn't be concerned, but if they enjoy fighting and rolling over each other and/or one sitting astride the other, or touching in wrong places, I would be a little bit concerned; not concerned that your son has SSA, but simply that he may be arousing his sexual feelings and nature, which can then lead to fantasy and addiction at a later stage.
In such a case, if there's a way you can mention to him somehow in a friendly way that it's not “healthy behavior”, it might be worthwhile (you may have to make something up here, like "it says in the sefarim that to sit on someone – or to “play doctor” is an aiyin hara" – or whatever ).
G-d luck.
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