Healing Entity When First Spawned

[qpwoeiruty]

I have an entity that can spawn with a different max health each time, but it only has the default 2 health that the default would have. I want to heal the entity when it spawns so it actually has full health and doesn't just appear to. I have tried doing it before but it doesn't seem like it wants to work. I also want to make sure that it doesn't happen again so it doesn't have a natural regen, just once when it first spawns.

[sequituri]

Show us the code you have tried that did not work.

Give us something to start with.