Step kid

So me and my bf have been dating for 5 months and before we were he told me he had a 3 month old little girl. Honestly I had no problem with that and still don’t to this day. If anything I adore this little girl and enjoy when she comes over to see her daddy for the time being. The situation with the baby and baby’s mom isn’t ideal for him of course cause he only gets to see her once a week. But I tell him all the time that things will get better and maybe one day she’ll be able to stay over for a night with him. I guess technically she is like my step kid in a way because I’m dating the dad. I was just wondering if anyone else my age or close is going through the same thing or has once before.