I "inherited" two 6 & 7 yr old step daughters when I married my wife. Their real dad who I knew from the local aviation scene died in a plane crash about one year prior. The girls were young enough to pretty much accept me as dad, but now that they are teens, I feel a just a bit tethered when it comes to decision/rule making. The fact that I am the only man in the household against three women probably equally to blame.
Looking back, I was a bit overwhelmed at first as a 30 yr old never married bachelor, but I have no regrets 10 + yrs later.