If the lioness is 12 years old, the hyena, half her age, is 12/2 = <<12/2=6>>6 years old.
The baby of the lioness is 12/2 = <<12/2=6>>6 years old, half the mother's age.
Five years from now, the age of the lioness's cub will be 6+5 = <<6+5=11>>11
The baby of the hyena is 6/2 = <<6/2=3>>3 years old, which is half the mother's age.
The hyena's baby will be 3+5 = 8 years old in five years.
Together, the total age of the babies will be 8+11 = <<8+11=19>>19 years in five years.
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