Feeding a baby camel husk can make it grow faster, this is not the case with baby zombie horses, as seen in this bug report, they are not meant to grow.
Steps to reproduce the issue:
Spawn a baby camel husk, feed it with rabbit’s foot.
Expected result:
It should not grow, as zombie horses don’t grow by feeding either.
Actual result:
It does grow normally, as if its a regular camel.
Reproduced in 26.1-snapshot-5.