Yes, although it dates back to a few years. We used the service from London City airport to Pau where my parents live. Our daughter started when she was 6 years old. She has no brother or sister so did it on her own and was fine.
The airline was very attentive and when I asked questions on twitter, they said they'd make a special note for the flight attendants to look after her even more as it was her first solo flight. All went very well.
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