I came across this poem about pet loss, and I thought it was beautiful.

We Have a Secret

We have a secret, you and I
that no one else shall know,
for who but I can see you lie
each night in fire glow?
And who but I can reach my hand
before we go to bed
and feel the living warmth of you
and touch your silken head?
And only I walk woodland paths
and see ahead of me,
your small form racing with the wind
so young again, and free.
And only I can see you swim
in every brook I pass
and when I call, no one but I
can see the bending grass.

-Author Unknown