Return ticket...but not using departure element

We are traveling Thailand to collect our 14yo Daughter, is it possible to buy 3 return tickets but for one of the tickets (Daughters) only use the return part?
Will the fact that she is not on the UK departure cause a problem, and affect the return journey back from Thailand?
The main issue is that we cannot book a single return for a minor to join us on our return flights, and don't really like the idea of paying a minimum 3 one way journeys on top of a return flight for one.
Any help on this or direction to someone that may know more would be appreciated.
Thank you
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Can you not use a departure ticket but use a return?
No, you cannot only use the return ticket. To guarantee that the airline keeps your return ticket, you are required to travel on the first part of your trip and all the way to your final destination.Can I only use the return flight?
The short answer, as many have said, is that you won't be able to use your ticket's return leg only. Once you skip your outbound flight, your return will be canceled.What happens if I miss a return flight on purpose?
If you purposely miss a flight then your ticket will be reallocated to someone on hold. You will lose the value of your ticket. The only reason I can think of that someone might miss a flight on purpose is that it's sometimes it's cheaper to book a muli-leg flight and travel one way or leg.Is it necessary to buy return tickets for family visit visa? Solution? | Ali Usman Ghani
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