Anthony Stubbs, 16, from Leyland, Lancashire, went missing from his home just weeks after becoming a father to daughter Lily with his girlfriend Charlotte Mason, 18.
The Year 11 pupil left his home around 1pm on Sunday November 25. He was heading to his mum's house close by, but never arrived.
Lancashire Police say the last confirmed sighting of Anthony was on Leyland Lane near to the Seven Stars pub at 12.55pm on that Sunday.
Distraught Charlotte has appealed for school prefect Anthony to come home. In an emotional statement she said:
"It's completely out of character for Anthony to go missing. We just want to know that he is safe, it is the not knowing which is so upsetting.
"We've been together for nearly two years now and this was Lily's first Christmas which I know Anthony was really looking forward to, he had even bought her a stocking before she was born. Anthony was so proud when Lily arrived, he is a great dad and I just want him to come home and give her a cuddle; Lily's missing her daddy.
"Anthony, we just want to know you are safe, please just get in touch and let us know you're ok."
Anthony found out he was going to be a dad when he was 15. He had just turned 16 when his daughter was born.
He is described as being of slim build, clean shaven, with blue eyes and around 5 feet 9 inches tall. His natural hair colour is mousey brown, although he dyes it black.
His hair is usually worn with swept fringe to the right or flicked up at the front, or sometimes shaved at the sides and spiky at the back and on top. He wears braces on his teeth and has a pierced left ear in which he wears a stud or a cross.
He was last seen wearing blue jeans with a blue and black jacket and light brown boots and carrying a black and blue messenger type shoulder bag. Anthony has connections to the Manchester, Bolton and Blackpool areas.
Detective Inspector John Entwisle said: "There have been a number of reported sightings of Anthony since we made our last appeal; unfortunately none of them have come to fruition. However, we are continuing to work through Anthony's contacts and speak to those who know him.
"I would urge anyone who thinks they may have seen Anthony or might know where he is to come forward and contact police. I would also like to make a direct appeal to Anthony: you're not in any trouble, we just want you to make contact with us or your family so that we know you are safe."
Anybody with any information can contact police on 101 or Crimestoppers anonymously on 0800 555 111 or online at Crimestoppers-uk.org.