Rebecca Aylward was reported missing after failing to return home Police are continuing to question two 15-year-old boys over the murder of a girl whose body was found in woodland.
On Monday South Wales Police were granted an extra 36 hours to hold them.
Rebecca Aylward, also aged 15 and from Maesteg, near Bridgend, died of head injuries and her body was discovered near Aberkenfig on Sunday morning.
The schoolgirl, described by her family as “happy, outgoing and bubbly” failed to return home after being dropped off to visit a friend.
She was last seen in Sarn Hill, Sarn, near Bridgend, at about 1230 BST on Saturday.
Police are desperate to speak to anyone who saw her after that time or spoke to her on a phone.
Her body was found at about 0900 BST on Sunday.
The results of a post-mortem examination found she had died as a result of head injuries.
South Wales Police said it would use “every snippet” of information to catch her killer.
In a statement issued via the force her relatives said: “Rebecca, also known as Becca, was dearly loved by all her family.
“She will be sadly missed, she was a very happy young girl, she had an outgoing and bubbly personality.
“As a family we are all devastated by her untimely death and wish to be left alone to deal with our grief in private.
“Becca can never ever be replaced.”
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