His body was found on a construction site in Worsbrough, near Barnsley, on Monday morning after he went missing on Sunday night.
Grandmother Deborah Fraser went to the site to pay tribute to Conley and said she was “shellshocked” by his death.
She said: “As a person he was a lovely little lad – boisterous, got into anything and everything but his smile could light up a room.
“It’s not even sunk in now that he’s gone. I’m stood next to the place where he died and I’m thinking ‘What the hell were you doing, Conley, in a place like this?’
Speaking about how Conley got trapped in the pipe, she said: “He slipped. You know it was raining, he slipped and went straight down. I hate to think what his little mind was going through.
“His brain must have been all over the place trying to get out.”
Conley vanished after playing with friends in Locke Park, a mile away from the site and about two miles away from his home in Barnsley.
He had gone to play at about 6pm on Sunday and was due to return home around two hours later.
Mrs Fraser said: “He’s been known to go in there (the construction site) before and we’ve told him not to go in. It was raining and we just expected him to come home. (His mother) is devastated, we all are. We will all miss him, he was a lovely little lad.
“We all knew that he had gone missing, but when you actually see it on the news and realise it’s your grandson that’s been found, then you’re shellshocked.
“He loved dinosaurs, he loved Ninja Turtles, he was just a typical lad. He like drawing and loved his PlayStation. He loved his life. He was a happy little chap.”
Last night South Yorkshire Police were still to confirm the body found at the site as being that of Conley.
Officers are understood to be treating the death as a “tragic accident”.
Wayne Bolton, who was with his son, Finley, four, said the first he heard was the helicopter being used to search for the boy on Sunday night.
He said: “It’s shocked everyone and everyone is in bits. Luckily, in an area like this, everyone comes together and we all help each other.”
Cheryl Dunning, the mother of seven-year-old Evan Dunning, who was friends with Conley and used to play football with him, said that the discovery of the little boy’s body was “sad, very sad”.
She added: “It makes it worse because he’s the same age (as her son) and everyone knew him.”
Detective Inspector Victoria Short, leading the investigation, said: “We deployed our full resources with officers searching throughout the night to find Conley and we are deeply saddened by this tragic development.
“While it is early in the investigation, the death is being treated as unexplained and a post-mortem examination will take place in due course.”
The Rev Trevor Keightley, vicar at the nearby St Thomas’ Church in Worsbrough, where a book of condolences is to be opened today, said: “Everyone’s feeling it at the moment and everyone is very upset about it all.”