Edgar - the Milne is wonderful and a lovely way of talking about things for your older daughter too.
I am so sorry that you are having to go through this.
I wondered if The Little Prince might be helpful for the service as it has some very tender reflections on love and loss in it. I don't have it here at the moment.
And I also wondered if you might like Derek Walcott's poem 'For Adrian' from The Arkansas Testament. It's written in the words of an 8-year-old boy he knew who died suddenly. It's a poem that I've taught to classes of children who've lost a friend and they've found it comforting at a very bleak time.
For Adrian
April 14, 1986
(To Grace, Ben, Judy, Junior, Norline, Katryn, Gem, Stanley and Diana)
Look, and you will see that the furniture is fading,
that a wardrobe is as insubstantial as a sunset,
that I can see through you, the tissue of your leaves,
the light behind your veins: why do you keep sobbing?
The days run through the light's fingers like dust
or a child's in a sandpit. When you see the stars
do you burst into tears? When you look at the sea
isn't your heart full? Do you think your shadow
can be as long as the desert? I am a child, listen,
I did not invite or invent angels. It is easy
to be an angel, to speak now beyond my eight years,
to have more vestal authority, and to know,
because I have now entered a wisdom, not a silence.
Why do you miss me? I am not missing you, sisters,
neither Judith, whose hair will banner like the leopard's
in the pride of her young bearing, nor Katryn, not Gem
sitting in a corner of her pain, nor my aunt, the one
with the soft eyes that have soothed the one who writes this,
I would not break your heart, and you should know it,
I would not make you suffer, and you should know it,
and I am not suffering, but it is hard to know it.
I am wiser, I share the secret that is only a silence,
with the tyrants of the earth, with the man who piles rags
in a creaking cart, and goes around a corner
of a square at dusk. You measure my age wrongly,
I am not young now, nor old, not a child, nor a bud
snipped before it flowered, I am part of the muscle
of a galloping lion, or a bird keeping low over
dark canes; and what, in your sorrow, in our faces
howling like statues, you call a goodbye
isI wish you would listen to mea different welcome,
which you will share with me, and see that it is true.
All this the child spoke inside me, so I wrote it down.
As if his closing grave were the smile of the earth.