When baby mobs such as foxes, chickens, zombies, and others jump while underneath a block (jumping up a block into a 1 block tall gap, such as certain cave walls and new 1-high houses) I have noticed them suffocating, and suspect the fact that jumping under normal circumstances propells the mob 1.25 blocks high, thus putting them briefly into the block above and taking suffocation damage. 

As well, this is NOT EXCLUSIVE to baby mobs. I have seen some mobs such as sheep and cows perform this, adult sheep and adult cows, and fully suffocate themselves. Other mobs like the chicken take what appears to be 1 half-heart of damage, and after 4 times of doing so perish, all the while under normal pathfinding.

I understand this report contains many similarities to other bugs, those solved and those not. I am trying to highlight ALL the mobs affected under this issue, and acknowledge SOME have been fixed, but many have not. Those which have not are why I am reporting this, and while I cannot think of all of them at once, I ask the community to confirm which have been fixed, and to add in comments which they have found that are also bugged.