How long is too long to be dating someone and have never met their kids?

I’d say a year or so 🤷🏼‍♀️ I never let ppl meet my kids unless there being serious if not I wouldn’t bother... all tho that wasn’t the case with my husband but he just acted differently towards them and I could tell he really liked them we were together a month before we got married goin on 6 yrs

Yes a year. On the flip side I would be concerned if they were introducing me to their kids if it was 3 months or less