Family members asking sims to the prom: Bug or feature?

[Gwill]

A while ago one of my teen sims got invited to the prom by his mother, an elder who lived on another lot.  I accepted without looking too carefully at the name and didn't notice before the prom started.  They seemed to hit it off, drinking punch and dancing all nigh.  I was worried they might get romantically involved, but thankfully this didn't happen.  His prom picture did confirm that he was indeed there with his mother.  I feared it might be a sign of impending doom, but no harm seems to have come of it and I forgot about it.
Just now I had something similar happen, in different game, a fresh neighbourhood; another young man was invited to the prom by his uncle.  This time I spotted it and turned him down.

Is this a feature designed to embarrass young sims who can't get a date themselves?
Is it a horrible perverted glitch?

[jezzer]

I always do the inviting, so I haven't seen this.

[J. M. Pescado]

Horribly perverted glitch. Sims have also been known to receive strange things from farm animals, so...

[socurious]

Does this only happen to extremely shy teens (or animals)? Perhaps it's a TS3 programmer's experience written into the code? Or, a glitch.

[Gwill]

The teen in question this time has the loner trait.  I can't remember how it was the first time.

Also, it looks like there is only one other teen in the whole neighbourhood, and she's a first cousin.

[socurious]

The teen in question this time has the loner trait.  I can't remember how it was the first time.

Also, it looks like there is only one other teen in the whole neighbourhood, and she's a first cousin.

'em er some slim pickin's thar, I tell ya'! Seems mighty reasonable if granny wants ta go to tha prom. hurr (craptastic!) har!

[coltraz]

Just last night I witnessed a Sim's grandmother invite him to prom.

Also on a similarly disturbing note, I recently had a Sim roll a want to skinny dip with her brother. I mean, what is this, season six of Dexter?

[PrinJess]

I realized that I couldn't use the romance interaction on my boyfriend because he was really my nephew; the damn Sim invited me to the prom and at the time I didn't know they were related. Inside the Friendly interaction branch there is a "worry about relationship" option. Isn't that usually reserved when a relationship is on the rocks from having low friendship?

Also, my Sim has the Loner trait. Hmm. I guess she's that desperate.