Relative to/in relation to / affection / terrified

Could you please take a look at this for me?

1 The bet was very big in relation to /relative to the size of the pot.
2 He's still a child in his affection towards his praents.

3 I'm terrified to think how many people are going to sign up for my summer camp.

4 You know the player is on a roll when he's not done raking in the chips he's won and already playing

for more chips that are about to come his way.

Thank you