Spawn NPC right

How can i spawn an NPC that they didnt remove after an little time ?

Well, if you spawn an NPC they should no move after a while. But try this :

.npc spawn (npc id) 1

So, say you wanted to Spawn some random create forever do :

.npc spawn 1337 1

With .npc spawn <id> my keeps too but they disappear after an little time,
and after an longer time they will come back and stay wtf

I dont know why they disappear xD