Im pretty new to MN so please be gentle 
I'll try to keep it brief if I can. OH and our family moved from our home town a couple of years ago. One of OH's friends and his DP had a young baby when we left. She had never been an organised or tidy person, but at the point we left the town, it was worse than ever. I don't mean a bit of normal mess and clutter, it was actually hard to navigate through the clutter, and the oven looked so unclean, it would make you ill to eat from it. OH's friend worked 70+ hours a week, came home and found nappies stuffed behind the sofa, kitchen piled high, and baby handed to him as he came through the door while she went to bed.
I thought maybe PND, so offered (discreetly) to help with the baby if she needed a break, but they have a good extended family and HV, so said they'd were fine.
Fast forward a couple of years, we've just visited family and friends in our home town for the 1st time since. Talking to a mutual friend, it turns out the couple are in a worse state than they were before.
I asked where are his and her extended family in this- apparently one set of GPs had the baby for a week, while the other GPs gutted the house- but it's back in the same state again now.
The child (now nearly 3) is still in the Playpen he was in when we left the town, because (I presume) it's the only bit of the house safe to be in. He has been walking since 11 months, how is a Playpen enough space, or healthy for a toddler to be in all day?
DH's friend said the couple never take the child out to any activities or nursery, he just sits and watches TV programmes from his Playpen.
I only found all this out yesterday night, and don't know what to do. OH's friend we visited, said he was shocked to see it. It was the first time she'd answered the door to him visiting in a while.
I just don't think it's right, that a nearly 3 year old child sits in a hovel of a home in his playpen, watching tv with the curtains closed. I don't think I should ignore it.
What would you do? Thank you in advance.