Key players in the Celtic squad;
— Harry Brady (@HarryBradyCU) April 30, 2018
Ajer turned 20 earlier this month
Tierney is 20
Ntcham turned 22 two months ago
Edouard turned 20 three months ago
Eboue is 20
Dembele is 21
21 - 23yr olds at other clubs are often called "promising youngsters"