Hail to you, Rules Guru !!Â

Well as said in this topic title, I have some questions about Nether Spirit and his "Return to play" effect :
1) If I have
Squee(s), Goblin Nabob with a sole
Nether Spirit in my graveyard, can I return the Squee(s) to my hand then the Spirit into Play ?!?
2) If I have
Undead Gladiator(s) instead of Squee(s), is it working the same way ?!?
3) If,
at the beggining of my Upkeep Phase I discard a Nether Spirit to return an Undead Gladiator from my graveyard to my hand, Does the Spirit return to play thereafter ?!
Squee & Spirit are triggered effect, Undead Gladiator's capacity is an Activated Ability, does they all go to the Stack ?
Thanks for your help.
Regards,
Soon.