It’s 90cm for the majority of the rides at legoland. We went last year because we were given free tickets and he really enjoyed the mini city of landmarks made from Lego and there were a couple of little rides he could go on and we watched a show, but I was glad we hadn’t paid for it
My son is 85cm as well and we are going next Sunday for his birthday. We have taken him before and he loved it. There is quite a few things for him to do and parks. He also just loves to walk/run around which I understand they can do anywhere but it's a new place he hadn't experienced before. We do have merlin passes though so don't have to pay to get in yet
We haven’t my boy is 91cm and we’re going to diggerland on Sunday for his birthday there they say 90 cm minimum for most rides I’m not sure what the height is for Lego land xx