I think you should not worry. I believe you planted a seed in her heart, and her dad's behavior was noticed by her. I'm confident she doesn't understand now, but when more pain enters her life (as it tends to do), I think that seed will still be there and I think he solidified the memory of you in her mind. Really, for all we know she might already have troubles at home likely being told what to think, and could be wanting to know what is being kept and hidden from her.
Things are not always what they seem, and I think you are doing the best you can to reach the children. There was no way to avoid her dad being there, as that was the reason she was there, and he should be as it is his child and I feel God will do a mighty work in spite of him (or maybe even because of him). Hatred toward kind people has a way of really impacting children when they start to experience bullying first hand, and every child experiences it to some degree. They remember people's reactions to things, and I believe you did more good than you likely feel like you did.
Also, prayer works. I'll pray for her with you. (and the dad and family, of course, lol)
Just some healthy reminders we must hold on tight to.
1 Peter 2:20
For what credit is it if, when you are beaten for your faults, you take it patiently? But when you do good and suffer, if you take it patiently, this is commendable before God.
Matthew 5:11-12
Blessed are you when they revile and persecute you, and say all kinds of evil against you falsely for My sake.
Rejoice and be exceedingly glad, for great is your reward in heaven, for so they persecuted the prophets who were before you.
Don't judge the outcomes. You're following the orders and His heart is in you.
May God bless you for what you're doing. Keep going! You're making a difference, God is using you powerfully. Don't doubt it!