Slytherin House / MALcolm BADdock / Eileen / Sorting Lily

[Ceridwen]

No: HPFGUIDX 185725

Pippin:
*(snip)*
>  Lily could have considered her Muggle blood inferior  and attributed
> all her talents to an unknown magical bloodline. In that case she
> might have been admitted to Slytherin just as Riddle was. 

Ceridwen:
When Riddle was Sorted, did anyone actually know that he was a
half-blood?  Or did it look like he was a Muggle-born Sorted into
Slytherin?  We don't know if the hat took some time to Sort him or if
it was like Draco, barely on the head before shouting out "Slytherin!"

If Harry's discussion with the hat is any indication, there is no talk
about ancestry, just placement.  If the hat Sorts by getting into the
student's mind, Riddle didn't know about any definitive Wizarding
ancestry.  He may have guessed, or suspected, or wished; that isn't
having assurance (like Draco had assurance) of such an ancestry. 
Wishes are not facts.  Dumbledore apparently didn't tell anyone about
Riddle's talent with Parseltongue so to anyone watching the Sorting, a
Muggleborn was Sorted into Slytherin and that didn't seem to create
huge ripples in the school or the WW.

Ceridwen.