backstory "explanations"

[finwitch]

No: HPFGUIDX 137535

Finwitch:

Others have pointed out the JKR telling us that James is definately 
Harry's father...

I'll just say that Snape's Worst Memory in OOP shows how James was 
most definately in love with LILY in his 5th year. So, unless Lily 
fed him Love Potion, that theory is way off...

Sure, Sirius&James were close as twins, which might be due to Sirius 
hanging on to James for moral support against his family. Leaving 
Black house for Potters definately shows something like that.

Also, I think that the reason why James could trust Sirius so 
*completely* is that as Sirius was made Harry's godfather, this was 
made with an Unbreakable Vow... but only James, Lily and Sirius knew. 

Finwith