WTF!!!

My niece doesn't have much computer savvy.
She has my old computer, which is still running Windows 95, at home, and at work she only has access to an email account.
So, anyway, I occasionally email at her work address where I send her pictures and we bad mouth other family members.
Last night I emailed her about a crazy thing that my sister, her aunt, said, and at the end I said:
WTF is up with that?
Today she emailed me back and asked if WTF meant what she thought it meant, and I told her that yeah it probably did, so all day today she was emailing me with
WTF this
and
WTF that
and
WTF this again
and
WTF that again
and
WTF
Ad Infinitum