To the OP - I really hope that things are improving for you.

I wonder if this is related? - A couple of times recently my child has basically been chased in Ladywell Fields (Crofton Park end) by a guy matching your description. I have also seen him at other times wandering around the park with a can of drink seeming pretty out of it. The guy says that he has 'seen children falling in the river' and that's why he's chasing them - let him have that as a random but I assumed harmless excuse last time but two times is enough and the second wasn't by a river so am going to report to non-emergency police.

So just wondering if it might be the same person and whether anyone else has come across him in the park?