Entrust them to God. Put them in his hands. Trust that his love for them is greater than ours.
What is really hard about that is knowing that entrusting them to God, who is utterly trustworthy, will not necessarily mean that they will avoid some of the things we would like them to avoid, or have all the things we might like them to have. It does not necessarily mean they won't be taken from us before we're ready (will we ever be?), or that they won't be led through hard and bitter times. It does not mean that they will have straightforward careers, or romances, or financial security.
It just means that we trust that God is good and will do them good.
When I struggle with this, it is because God's goodness is so much stronger, and his love so much more penetrating, than mine. He will do good, even if it hurts. He will love, even if that love looks like breaking us. I realise that at some level I don't want that for my children. I realise I don't want it for myself. I am comfortable with a nice, middle-class, not-too-extreme goodness. I like it when people seek my good, so long as they are not intrusive about it. I enjoy sensible, middle-class love, which doesn't impose itself or go beyond the boundaries I set for it.
In short, I like others to be good and loving to me so long as that leaves me pretty much as it found me and doesn't threaten my sense of comfort and self-satisfaction too much.
The goodness of God is so much fiercer than I can handle! The love of God is so much deeper than I can fathom! He wants to - is determined to - do me good, as defined by his all-knowing wisdom. He wants to - and in Christ has given everything to - show me love, the kind of love that completely reshapes the loved in the beautiful image of the lover. He wants to make me holy and righteous and good and bring me into his presence forever; I want him to make me comfortable and happy and good-ish and make me secure in myself for now. I want his goodness and love to scale themselves down to my terms.
Instead, I am given Jesus. And he is good. And I can entrust myself and my children to him. Because he is love.