Cardinal Timothy Dolan knew at the age of three. He and his brother (Bob Dolan) tell stories of how all who knew young Timothy encouraged his faith and vocation. So, yes, it is possible.
My 13 yr old has said since he was 5 that he’d like to be a priest. He rarely mentions it now, but he still loves to go to the seminary for camp and events, so I know he still ponders it, he’s just busy growing up right now to be as open as he was when he was 5 & 10 yrs old. My oldest daughter is 3 months away from making her oblation. She was miss fashion and social butter fly as a child with no mention of a vocation. By 8th grade she still didn’t know her vocation, but wrote as her graduation letter (tradition at the school she attended) that she did not know if she’d be a mom with many kids, (adopted or natural) or if she would be celibate. The main point was that she kept her heart and mind open to God’s call which she eventually heard and has gone on to pursue.
As a parent all we can do is offer prayer and mortification for our children’s vocations. Keep the option open as a choice in life so they are aware of the need to discern and listen to God’s call. Another big part we must also realize is that no matter what we do, we do not create a vocation. We only can create an environment that nurtures fidelity and faithfulness to God. Your daughter DOES have a vocation, and that is to Love and Serve Our Lord. As she grows she will learn from God how she is to live out that vocation. She may end up taking religious vows or she may end up being the mother to priests that we need. Keep taking her to adoration and she will grow up listening to God and perhaps hear her vocation early.