I love this one that my kids learnt at nursery

Hee-haw, hee-haw
does anybody care
There's a baby in my dinner
and its just not fair

Jesus in the manger
lying in the hay
far too young to realise
he's getting in the way

I don't blame the baby
not his fault at all
but his parents really should respect
a donkey's feeding stall

After all that journey
with my heavy load
did I ever once conplain
about that dreadful road

I can cope with the backache
and these swollen feet
all I ask is some respect
and one square meal to eat

"Be prepared", I told them
better book ahead
Joseph said "Don't be an ass"
and took a chance instead

Now they've pinched my bedroom
people are so rude
I can cope with that but not
a baby in my food