Definition: In this task, you are given a Reddit post as a text. Your task is to generate a title for this text. The title should start with "TIFU by", followed by a situation that caused humor. The title should contain 7-12 words, ideally.
Input: Text: obligatory: this happened my sophomore year of high school, which was a couple years ago.

first some background info. the high school i went to had an engineering pathway, which was taught by a teacher, who we will call mr. w. mr. w's wife taught 7th grade english at the middle school i attended. i have a younger sister who is three grades below me, who at the time this happened, was in mrs. w's english class. about midway through the year, mrs. w got very pregnant, and the school gave her some time off. they had to hire one of those long term substitutes and all that fun stuff. needless to say, this was pretty big news to my sister, as she talked about it all the time at home. 

anyway, now for the fuck-up. 

one day in class, mr. w was showing us a funny video of his other daughter (who was 4 or 5 years old at the time) learning to ride a bike. for whatever reason, i didn't realize that mr. w had two daughters, one that had been here for awhile and one that his wife was recently pregnant with. in my mind, i thought that the girl that was trying to ride a bike in the video was the same girl that should've been born quite recently. so me being the ever-observant, genius that i am, i raised my hand and said something along the lines of, "wow, your daughter sure has grown up fast mr. w." he gave me a confused look and said, "what do you mean?" i replied, "is this your only daughter?", to which he said "yes". but it didn't stop there, oh no. i kept going, and at this point the whole class is looking at me, in dead silence. now i can't remember exactly what i said, but it was something like "i could've sworn that your wife was pregnant just last year. how is your daughter already learning to ride a bike?" finally, at this point, the girl who was sitting next to me in class lightly elbowed me in the side and said softly into my ear, "[my name], mrs. w had a miscarriage." 

as this entire exchange had been going on, mr. w had an expression that i cannot really describe. it was a mix of confusion, sorrow, anger, and a whole bunch of other emotions. 

so after my neighbor said that to me, it all suddenly clicked in my brain, and i nearly instantly felt like the worlds biggest asshole. i meekly said "nevermind", and tried to sink as low into my chair as my 6,1 frame would allow. i just wanted to melt, i felt so bad. to this day this remains one of the biggest moments that i wish i could travel back in time and just punch myself in the face, save me from the embarrassment. i still don't know how i didn't know about this earlier.

mr. w didn't have any hard feelings towards me. i think he understood that it was truly an innocent mistake, that i wasn't being intentionally malicious or insensitive. i was just an idiot. he actually got a promotion later that year, and stopped teaching at that particular school.

**

TIFU for not knowing about a teachers miscarriage