Turley admitted to the killing, while Stewart and the 15-year-old were found guilty of murder last month following a trial at the High Court in Glasgow.
All three had been members of the Murray Boys group, while Kayden and others were part of the Himshie group in East Kilbride.
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In a message on social media posted ahead of the sentencing, Kayden’s father Paul Moy said: “Nothing that happens in that courtroom will ever bring our son back.
“No sentence can fill the emptiness, the heartbreak, or the lifetime of memories we’ve been robbed of.
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“Forever loved. Forever missed. Forever my son.”
During the trial the jury heard that shortly before the attack Turley, Stewart, and the 15-year-old had been at the top of a sand dune throwing rocks at people on the beach.
Kayden’s girlfriend Keryn Knox, who had been with him at the beach, said they had been getting ready to leave at about 6pm when the rocks started to be thrown, and Kayden had gone up to confront the teenagers.
Ms Knox told the court: “I went up with him to try and stop him. At that point he had run up the hill and he was just shouting stuff back.
“Then Cole ran in from the side and Kayden has seen a blade and when he tried to run he slipped, and when he tried to get back up Cole has stabbed him in his left lower side twice.”
The witness said: “Then out of nowhere Cole (Turley) just started running at us. I ran to the right, so did Kayden, I jumped over a grass ledge, Kayden slipped and Cole leaped over and jumped on him.
“He had a knife and it hit. I saw one stab.”
The 16-year-old was so badly injured in the attack that he later died.
Stewart and the 15-year-old had denied the murder charge and had lodged special defences of incrimination.
However this was rejected by the jury, who found both guilty of Kayden’s murder after a trial lasting more than two weeks.
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