@KoiwiGal - That is really sad. How awful for his poor parents. I think that if a child has unexplained bruising, they should always get checked out by a doctor, just in case.
Because, of course, it could be abuse as well. There's no way to tell unless someone cares enough to look.
But, you should also remember as it says in the article, that people bruise more easily as they get older.
My mother bruises if you tap her on the shoulder. She's asked the doctor about it and it's just that she is getting old and has very fair skin.
She is more embarrassed by it than anything else. She uses up a lot of bruise cream, trying to get them to go away.