I've had the same with T & P for over 15 years now. Somedays it seems really bad and somedays I don't notice it at all. Tubby is the jealous one and he usually wins the battle because he's bigger, but I always try and find special time with Peanut when Tubby's not around so she doesn't feel rejected.
The biggest thing that helped me is that I moved in with Terry. Don't know if adding a partner to your household is an option
but I really believe that this is why Peanut has become such a daddy's girl. Mom was always monopolized by Tubby, so Peanut went to daddy for attention instead.
I know this doesn't help you much, but like I say, somedays are better than others, so if you just make sure they both get adequate alone time with you, there should be no lasting resentments or anything between them.
Good luck!
Tubby
Spring 1986 - Dec. 11, 2004
RIP Big Boy
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Peanut
Fall 1988 - Jan. 24, 2007
RIP Snotty Girl
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Robin
Fall 1997 - Oct. 6, 2012
RIP Sweet Monkeyhead Girl
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